Android Battery Saving Tips

Here my list of battery saving tips given my experience of helping many with their Android phones.

Know that the major culprits for affecting battery performance which we try to minimize the impact of are as follows:

  • system components known to use a lot of power such as the GPS, mobile data or the screen being used extensively
  • background activity that prevents the device from entering a power-saving sleep state, usually with specific applications

10 tips that work

  1. Avoid running the screen at higher brightness setting than necessary by ensuring that automatic brightness is enabled for indoors use and possibly avoiding use outdoors. The screen timeout setting should be under 2 minutes, and for most people the default factory setting should suffice.
  2. Ensure maximum cellular signal reception as much as possible. Low signal strength causes the phone to chase for one and waste battery in the process. If you are in an area without reception for an extended period of time, consider toggling on airplane mode. Leave the data speed be the default with all the modes enabled, applying to most recent phones out there.
  3. Reduce background activity
    1. Turn off all unnecessary push notifications and synchronization services from the settings portion of the application. You can tell in part when your notification bar is mostly clear of notification items as you use your phone, without having you to clear them
    2. Remove any unused widgets from the home screen
    3. Use a static wallpaper instead of a live wallpaper
    4. Disable or uninstall unneeded or misbehaving applications. OS Monitor and Greenify are good tools for finding misbehaving applications together with to the built-in Android battery settings tool. Facebook and Google Location History are several known culprits for having significant impact on battery life. It may be better to use to the mobile version of a website by visiting it from your web browser, rather than to install a native Android application in order to avoid impact to your device.
    5. Remove unused data synchronization accounts or disable data synchronization configured. Use manual synchronization whenever possible and reduce the frequency of automatic synchronization
  4. Swipe away and fully exit applications you do not need to return to, when you are done with them for good
  5. When performing battery draining activities, connect the device to power. Some applications Google Photos backup have an option to only perform photo and video backup when plugged into power
  6. Reduce GPS sensor activity by disabling use of this feature on application or system level. Alternately kill the offending applications as soon as you are done with them.
  7. Prevent built-in media scanner (Mediaserver) from doing excessive work by adding ‘.nomedia’ files to storage device where files are frequently written to, such as into the default download directory ‘Downloads’. Ensuring there are no malformed tags in your audio or video files if manually adding these to your device. See also this article
  8. Disable Google+ and its profile synchronization features if you can get by without this. Correct contacts synchronization errors when they appear by ensure that there are no malformed contacts. This can be done by running Contacts Sync Fix periodically. This only affects certain devices.
  9. Disable unnecessary accessibility features which are known to impact battery usage such as display color modes, device administrator applications, Samsung features such as smart stay
  10. Turn on WiFi and have it connected to a service with internet as much as possible if you have mobile data, so it uses WiFi as much as possible

Aggressive tweaks

  • Turn off mobile data when it is not needed together with WiFi to stop all network activity. This can be done at night, but I personally cannot recommend this for practical purpose.
  • control misbehavior applications – use Greenify in root mode
  • eliminate background activity  – use Power Nap for Xposed before Android 6 Marshmallow, or Greenify’s aggressive doze mode which does not require root after Android 6

So so advice

  • disable sound, vibration , haptic feedback – these features don’t drain that much power, and is usually just overkill
  • disable transistion and window animations from developer settings – I do this myself as a performance tweak, not for saving battery
  • reduce screen timeout – changing this from 2 minutes to 30 seconds can actually make it worse because the user may end up having to toggle the screen power more often, which actually increases system activity
  • keep your phone cool – a warmer phone actually ends up saving more power because phones are designed to throttle down in speed when they overheat, thus consuming less power, but note that this is NOT advice to warm up your phone
  • power saving mode – this is an aggressive setting that can ends up significantly reducing the functionality of the device, and it depends on the device’s implementation of this feature. Better off leaving it disabled.
  • use a black wallpaper – most devices aren’t on their home screen for very long, and you need a specific type of display to take advantage as well as clearing the home screen of any icons which are not dark enough. Practically this is pretty terrible advice unless you are changing the lockscreen wallpaper combined with the use of ambient display.
  • install custom firmware – making further customizations will not guarantee better battery life and often results in reduced device stability and functionality. I will not go into this on an in-depth basis here because I believe there are many other guides that cover this elsewhere.

Promising Smartphone Trends in 2016

While 2015 would be considered a year of stagnation in the world of Android based smartphone hardware for some, largely due to disappointing high-end applications processors from Qualcomm, the year for 2016 should on track for consumers to regain confidence in the platform improvements in both power efficiency and performance.

Power Efficiency with SoC Die Shrinks

The move to 14 & 16 nm manufacturing continues to promise to reap great benefits for power efficiency in the year of 2016, with more manufacturers shipping their SoCs based on the updated processes.

On the application processor side, Snapdragon 820 promises major performance-per-watt improvements over its predecessors. Qualcomm should have their X16 modem chipset available this year to further improve efficiency.

Samsung launched the Exynos 7 Octa 7420 with a 14 nm applications processor in 2015, typically configured with the modem part at 28 nm with Samsung Shannon 333 or Qualcomm at 20 nm. The Exynos 8 Octa is expected to launch with the application processor and modem at 14 nm this year. Intel’s Atom applications processors have been on 14 nm for quite a while now, but their XMM7460 modem is supposed to be available late this year.

14 &16 nm manufacturing technology is starting to reap benefits for other chip vendors as well in HiSilicon’s Kirin 950 and Mediatek’s X30 platforms.

These change hopefully lead to significant improvements in battery life under mobile data workloads in more devices.

Performance Improvements with Sufficient Memory

Android device hardware for this year finally seems to be inline with what is needed.

There were still many devices released in 2015 which were not equipped with enough RAM, which resulted in significantly reduced system performance. For example, the Canadian LG Stylo released in 2015 had only 1 GB RAM before other allocations. However, at CES 2016, LG’s newest mid-range all seem to have sufficient memory (1.5 GB) on paper to be able perform well from a performance perspective.

Intel released a memory tuning guide in August 2015, and this finally seems to be consistent with what manufacturers are equipping their devices with today:

Density and Screen Size 32 Bit Device 64-Bit Device
Android Watches 416 MB Not applicable
hdpi or lower on small/normal screens
mdpi or lower on large screens
ldpi or lower on extra large screens
424 MB Not applicable
xhdpi or higher on small/normal screens
tvdpi or higher on large screens
mdpi or higher on extra large screens
512 MB 832 MB
400dpi or higher on small/normal screens
xhdpi or higher on large screens
tvdpi or higher on extra large screens
896 MB 1280 MB
560dpi or higher on small/normal screens
400dpi or higher on large screens
xhdpi or higher on extra large screens
1344 MB 1824 MB

– Minimum physical memory required by kernel and user-space in Android 5.1 (Intel Aug 2015)

Display Improvements

Look forward to more consumer devices adopting improvements in display technologies including IGZO and LTPS displays.

Other Trends

  • NAND storage speeds have gotten ‘good enough’ for most devices released in 2015 even on generic devices, and should no longer be of concern in newly released devices
  • Android 6 reintroduces the ability to expand internal storage using microSD expansion as well as significantly increased standby battery life, and should be considered compulsory
  • In 2015, we saw significant improvements in image quality for smartphones across all manufacturers, and this year should be a continuation of this trend. The major areas of improvement to look for are in low light performance, focus speeds, and video stabilization
  • Google will be looking to proliferate Android Pay, so look for devices equipped with fingerprint sensors and NFC to take advantage

2014 – The Year Android Manufacturers Forgot to Make Good One-Handed Smartphones


Image generated from MobileDeviceSize

2014 is coming to a close, and that also means time for X’mas and gift giving, and maybe time to upgrade from an older phone. If you are an iPhone user, your choices are simple – the iPhone 6, or the 6 Plus? By now most people have figured out that the 6 Plus is too large for them, mostly because they can’t use it in one hand.

If you are an Android user, the choices are abundant as always. You have a lot of phones between the size of the iPhone 6 and the 6 Plus this year. Surely we can choose a flagship Android device this year that is passable for one handed use that compares to the iPhone 6, or can we? Well…

There are almost no new flagship phones available for one-hand use for the 2014 holiday season (in Canada, anyway)

One question everyone should ask is ‘how big do I want to go’. The bigger the screen, the more content it shows. Apple also picked their the mainstream model to be at 4.7″. But past this 4.7″ ‘ish’ screen, it is going to change the way you can use your phone. You are going to find that you will need to use the phone with two hands, because the on-screen elements are going to start to become out of reach.

If you pick a phone bigger than 4.7″ ‘ish’, prepare to give up being able to use the phone in one-hand. This is the threshold for one handed use. 

The top/bottom bezels of the iPhone 6 dominate the front of the phone much more so than the Nexus 5, and as a result the Nexus 5 squeezes in almost .3″ worth of screen estate without making the device significantly larger. Yes, it’s that hardware button. So I still would call everything up to the Galaxy S5 as a phone in this category.

So, up to around 5″ is still ‘okay’ for one-handed use

I have moderately large hands, and currently use a LG G2 with a 5.2″ display and very thin bezels. This is the largest I’d be comfortable with using in one hand – I’d even say it’s somewhat of a bit of a stretch for me.

What’s available this year for Android flagship phones at this size anyways?

When it comes down to what’s available, if you are going to get a carrier subsidized one-hand usable phone on the big 3 carriers. Well what sucks is that you have JUST TWO phones you can pick that are flagship devices at this size:

Samsung Galaxy S5 or Motorola Moto X (2014)


Generated by from PhoneArena

Effectively we have no-shows from the likes of LG, Sony and HTC. The Moto X for some reason is ONLY available in the 16 GB variant with no memory expansion capability, which makes it tough to recommend. Samsung is crazy for putting hardware front buttons on a flagship Android phone.

So what if I don’t like the Moto X or the S5? 

Well, either get the last year’s flagship LG Nexus 5. Or the alternative is to go for one of the bigger phones, but at what cost?

The HTC One M8 and Xperia Z3 don’t have much larger screens than the Nexus 5 or the Galaxy S5, but they put more bezel at the bottom of the device. This means you have to stretch further to get to the top edge to the display.

Phones with curved edges and curved backs let you wrap your hand around them more ergonomically. Softer rubbery plastics are also more grippy than aluminum or glass, examples being the back material on the soft touch plastic Nexus 5 versus the slippery aluminum HTC One M8. The flatness of the Xperia Z1/Z2/Z3 can result in hand fatigue after a short time.

Phone bottom bezels being thick, edges being sharp, back being flat, and having a slippery material make the phone more difficult to use in one handed use.

Here is a neat study on how people typically deal with larger screen sizes, and the different hand grips people use. You are going to be sliding your hand on the back of the phone to reach for the different parts of the screen, which can be tricky. You can alleviate this a bit by putting on a non-slip case, but then you are adding bulk to the device, so be careful not to pick a really thick case if you can help it.

Getting a case can help you adjust to having to use a bigger phone

Ending words: Hopefully the manufacturers and carriers will come to their senses and start giving consumers viable choices for 4.7″ ‘ish’ sized phones with good specifications. 2014 has been somewhat of a disappointment.

Upgrading from a Galaxy Nexus

Galaxy Nexus

In the past month, Koodo mobile had a sale on the recertified Nexus 4 for $150 pre-taxes, so I finally pulled the trigger for an upgrade. I had been using the Galaxy Nexus for 1.5 years, having purchased it from Rogers when I switched to Wind mobile.

In short, when buying a new Android phone in 2014:

  • Look for 2GB of RAM or more
  • Buy from a major manufacturer, and be sure to check the disk speed (read and write)
  • Get a newer model with a power efficient chipset


On paper, the Galaxy Nexus still has mid range specs: the second greatest version of Android with 4.3 Jellybean, had a 720p HD display at 4.65″, 1 GB of RAM, and a CPU/GPU that is on par with regards to performance. It would appear to be very close to the likes of the Moto G, which has rave reviews and has been gaining popularity because of its attractive price point of about $200 for the 16GB variant. What gives?

The Galaxy Nexus was a great phone for its time, but it had some glaring flaws. For me personally, what drove me to ultimately upgrade was:

  1. Lag, lag everywhere… Despite having all the right specs on paper, I was experiencing significant lag everywhere despite being pretty light on the phone.
  2. Battery life wasn’t enough for my usage patterns… I couldn’t make it through a workday without having to recharge my phone.
  3. Discontinued support… Grim outlook for 1 or 2 improving significantly in the near future

Let me explain…

  1. Lag: On a smartphone, in addition to making phone calls, you expect to be using Internet connected services. Those services run in the background and consume resources on the device. Android has come a long way since its conception, where the first device shipped with 100MB of available RAM. Now when it comes to the Galaxy Nexus, it may sound like 1GB has to be enough, increasing the amount by 10 times over the span of just 4 years. Unfortunately, this isn’t the case with the operating system consistently consuming more than half of what’s left. Out of the box, a portion of this memory is usually reserved for hardware components, notably the GPU, the radio baseband, and the camera – around 300MB worth. Now this number ranges depending on the device, but on the Galaxy Nexus, it was crippling the device performance with other services running on the phone. Once the phone starts running out of RAM, it actually has to work to remove things from RAM in order to keep doing what it’s supposed to. This process, called garbage collection, is one of the key contributors to stuttering in Android. The second contributor is – if applications can remain in RAM in a ‘standby’ state, they will be launched faster than if they had to be launched from scratch from a ‘cold boot’ from the disk, because RAM is much much faster than the disk memory. This means that this process is dependent on how fast the device can read from the disk memory. Unfortunately for the Galaxy Nexus, the disk memory is magnitudes slower than what its supposed to be, leading more more lag. On newer devices from major manufacturers such as Samsung, they make sure that the disk memory is quick enough. The same cannot be said for the likes of Huawei or no name brands. Despite Android 4.4 KitKat having lower requirements for RAM, I do not recommend any less than 2GB of RAM on a new smartphone, or it is guaranteed to be a mediocre experience. 
  2. Battery: While this isn’t a published spec, the Galaxy Nexus has a less power efficient package that results in an average of 1.5 hours of screen-on time in most scenarios. Smartphones in 2014 typically are capable of at least double this figure, but this is not a published spec. It is good to check review sites such as AnandTech for the WiFi browsing time, 4G browsing time, and 3G browsing time for the specific device. Newer models have newer chipsets, which are much more power efficient than older models. It is useful to know what chipset was released in the last while to know the difference. Or you can just go with a huge battery, but that also means you will end up with a bulkier device.
  3. Support: The Galaxy Nexus runs off a Texas Instrument CPU/GPU combination. Texas Instruments’ mobile division had gone belly up, meaning that there is no more software support from the manufacturer. Google stops their commitment for upgrading their software after 18 months. This means that the hardware issues in #1 and #2 will no longer improve with some sort of software fix. Here’s a good diagram by HTC (




Android Play Store Content Ratings are Almost Useless – Too Many Apps are Indiscriminately Rated for ‘Everyone’


A Mobile Casino Slot Machine App Rated ‘Everyone’

The app shown in the screenshot is Slot Machine Free Casino Slots, a free app on the Android Play Store. I am starting off with this offender because it highlights the severity of the issue.

This app is a slots machine simulator. Link to a YouTube trailer is here. Social features include logging into a Facebook or SOFTGAMES (game publisher) account. You can spend real money just like you can at a real slot machine. The part about gambling is where it is a gray area, because clearly this facilities real gambling and turns your smartphone into a mobile casino, as it allows users to spend real currency, but the app store is full of apps like this. The app at least should be rated with a ‘Medium maturity’ content rating.

Here’s a screenshot of their mobile web app showing cost of the virtual currency purchase screen, where Google will gladly take your money via Google Wallet:


What are Content Ratings for the Play Store?

A version for developers is available here, and here’s the section specific for gambling:

Apps that facilitate real gambling are not permitted in Google Play. Apps with gambling themes or simulated gambling must be rated medium maturity or high maturity.

The Play Store content ratings guide is quoted below:


Applications in this category should not collect user’s location data or contain objectionable material. Applications should not share user content or include social features.
Low maturity

Applications in this category may include instances of mild cartoon or fantasy violence or other potentially offensive content. Applications may collect user location data for the purpose of providing location specific information or otherwise improving the user experience, but should not share the data with other users. Applications may include some social features but should not focus on allowing users to find and communicate with each other.
Medium maturity

Applications in this category may include sexual references; intense fantasy or realistic violence; profanity or crude humor; references to drug, alcohol and tobacco use; social features and simulated gambling. Applications may collect user location data for the purpose of sharing or publishing with the user’s consent.
High maturity

Applications in this category may focus on or include frequent instances of sexual and suggestive content; graphic violence; social features; simulated gambling; and strong alcohol, tobacco and drug references. Applications may collect user location data for the purpose of sharing or publishing with the user’s consent.

Google’s Blind Eye to Real Gambling in the Play Store

Google’s position so far is to allow apps like this, as I am not aware of any app takedowns because of faciliting real gambling in apps, despite explicitly allowing gambling in the submission policies. Apple is different in that it allows for real gambling apps only certain geographic areas, and all apps are subject to approval before launch.

At the very least, Google is protecting themselves by making sure that developers are agreeing to the guidelines set out by Google, so it is ultimately not Google’s responsibility to the problem of gambling in the play store.

When apps are submitted, developers will see the following in order to consent to Play Store guidelines:


Even ‘Top Developers’ Offend – Case in Point: Yahoo

Moving on from gambling, let’s talk about private user data.

Yahoo has many apps under its portfolio. But I’ve discovered that they have been sloppy at keeping content ratings relevant for some of their apps, particularly for their Fantasy sports apps. They currently have 14 apps published.

The Yahoo Fantasy Basketball and Yahoo Fantasy Hockey apps are rated ‘Everyone’. But they both contain social messaging features that should automatically put it in the ‘Medium maturity’ category.

Here’s a look at the Play Store page:


The screenshots even show social messaging features:


If you go to Yahoo Sports and view their terms and conditions, they clearly state that they will collect user personal information:

By signing up for Fantasy Basketball, you agree to Yahoo!’s use of your personal information as described in Yahoo!’s Privacy Policy, located at

Apps Rated as ‘Everyone’ Collect User Personal Data, Including your Location – Case in Point: Electronic Arts Inc.

Here’s an example offender of putting apps in the ‘Everyone’ category – by Electronic Arts. Currently the 3rd top paid app in the Play Store. Need for Speed™ Most Wanted is rated as an ‘Everyone’ app, but has a terms and conditions of the app clearly states the application developer will collect your personal information, which is supposed to be non-personally identifiable, including your location:

2. Consent to Use of Data. To facilitate product support, product development and improvement as well as other services to you, you agree that EA or other third parties may use cookies, web beacons and other analytic technologies to collect, use, store and transmit non-personally identifiable technical and related information regarding your mobile device (including unique device id or UDID), IP address, geo-location, device make and model, operating system, software and applications, including application usage data. In addition, EA and/or third parties may collect, store, use and transmit non-personally identifiable game play data, session data, browser identifiers, carrier information well as online and Application usage metrics, statistics and/or analytics. Data collected by third parties will be collected, used, stored, transferred and disclosed pursuant to the third party’s privacy policy. See Appendix A for a non-exclusive list of third parties that may collect data via this Application. Appendix A includes both analytics companies and ad networks discussed in more detail in Section 3, below and includes URL’s for those third parties’ privacy policies and opt outs (if applicable). For data collected by or transferred to EA, EA may collect, use, store, share and transmit this information to third parties in a form that does not personally identify you in accordance with EA’s Privacy Policy located at

Here’s a screenshot of the app in the Play Store.


Electronic Arts is one of the largest publisher of games in the Play Store, yet a quick look at other games in the portfolio shows the same problem, most if not all of their games fall under the same terms and conditions, but yet are all have a content rating of ‘Everyone’.


Google Doesn’t Seem to Care Much

There doesn’t seem to be an easy way to the content rating of apps on an Android device. Here’s what it takes to view the content rating of an app on an Android device. Google has hidden this information underneath the ‘Description’ tab.


The main way to report apps is through the Play Store, but this only works through the Android app, at the bottom of the app page as follows. You inexplicably cannot do this in a web browser:


Google’s primary source of revenue is advertisement and selling your data, but I really believe that we should expect better of Google for this specific issue.

As a side-note, the Play Store’s Google+ integration is a content rating breach, because messages are posted publicly to the application’s profile. With app developers responding back to users, it is effectively a social messaging system. You can’t flag the Play Store as inappropriate though.

Ending Remarks

There are countless examples of apps that will collect your personal data, but how many of them are rated appropriately so you can keep yourself from using these apps?

For now, setting the content filter in the Play Store app is almost useless. Apps rated for ‘Everyone’ can and will collect your personal data, or even facilitate gambling.

If your children own an Android smartphone, there isn’t really simple solution for stopping them from using the Play Store and being exposed to inappropriate content in apps and personal data collection.

Currently, there doesn’t seem to be an easy way to check for offending apps from Google. I recommend this free third-party app I came across recently – BitDefender Clueful. Here’s a link to their app on the Play Store. The app analyzes the list of installed applications on your device and shows you how your private data is being utilized.

The strange thing is that they haven’t published a privacy policy for their application yet, but BitDefender historically does not sell collected information to third-party. By using Clueful, you do end up transmitting some data back to BitDefender. This is from their webpage privacy policy:

Information about our customers is an important part of our business, and we do not sell it to others. We share customer information only with the subsidiaries of BITDEFENDER, business partners or affliliated companies.


Buried in Smartphones Hardware Specifications for 2013

Smartphone hardware has been progressing fast, but this year, we are starting to see more new confusing things regarding hardware specifications. It is turning into what the PC market has been like for years, where most people have stopped caring about the specifications because there is such an overwhelming amount of information out there. Instead of hard specifications such as clockspeeds and bandwidth, people care most about what’s on the surface and branding.

For PCs, you want an Intel i5 or i7. Some people might know how many cores a processor might have, and rarely someone might know the clockspeed. You won’t find many people who know the actual processor names. For phones, people only know devices on a model name basis. For the majority, these hard specifications no longer make an impact on how they use their computing devices on a daily basis, and they stopped committing their minds processing the excess of information. The first thing people talk about is how big the screen is, how good the things, and maybe the storage. After that, they might count the number of cores it has or how many megapixels the camera gives them. This is also how manufactures get away with getting rid of the user replaceable battery, and concealing the whole thing in tape so it can never be repaired.

In 2013, the smartphone is really converging into the same pattern, where users see less and less benefit with getting the best hardware on the block. Qualcomm has already done their homework and is working to push Snapdragon as a branded platform, trying to emulate Intel’s success at marketing over the years. Compared to the likes of Nvidia and Samsung, Qualcomm stands out because they have started to market the Snapdragon brand as a complete platform, not just as a single application processor, and are one of the few manufacturers capable of doing so. At the end of the day, this mess isn’t necessarily good news for end-users, because more marketing doesn’t really equate to better products at all, and maintaining the proper balance here is a fine line to tread.

Here is a short list of some hardware specifications for computer geeks to know about that will get buried this year:


  • ARM Cortex-A15/Cortex-A7 big.LITTLE 4×4: being called octacore everywhere when it isn’t designed to run with more than 4 at any given time
  • ARM Cortex-A7 quadcore: this isn’t expected to perform that much better than a pair of old Cortex-A9s, but can have good power efficiency
  • ARM Cortex-A9 r4p1: a new revision that should bring about similar performance to what Qualcomm is squeezing out of Krait, coming the second half 2013
  • Intel Atom: a single core does as well as several ARM-based ones, but Intel isn’t keen on selling cheap chips
  • Fabrication process: hopefully your next application processor was fabricated at either 28 or 32 nm, because everything else is ancient by now


  • LPDDR3 vs LPDDR2: LPDDR3 bringing significant power savings and graphical performance improvements with the increased memory bandwidth, but Samsung might be the only
  • one using it since  they make these
  • Baseband envelope tracking: expected to bring significant power savings to celluar radio
  • Inflated screen resolutions: resulting in poor gaming performance, despite all the ravings about how much PPI you can squeeze out of a screen
  • Shrinking internal storage:  some manufacturers pushing a device with 16GB of internal storage all the way down to just 60% at 9GB (Samsung Galaxy S4)
  • GPU performance: this is a mess I have not spent a lot of time looking at, but a lot of things can go wrong here with graphically intensive applications
  • RAM: this has always been an issue ever since the G1, since manufacturers count memory allocated for crucial components such asthe GPU and radio chipset and unavailable to the operating system in this count. With larger screens that do more graphically intensive work, you need more RAM for the GPU. This so far hasn’t been a big issue though since Android is pretty efficient at managing lack of memory.
  • Storage technologies: we never see any information regarding to this, but it matters. Look for those IO benchmarks when considering your next purchase.


What is BusyBox for an Android user?

When a phone is rooted, one of the most common things to do after rooting is the installation of the BusyBox binary, prior to running any applications that require root privileges.

To make sense of this, it is necessary to have a brief understanding of what BusyBox is. BusyBox is a collection of powerful command-line tools in a single binary executable that can be run for UNIX based systems, including Android. The collection of tools available depends on how the BusyBox binary was built, and the source code is GPLv2 open-source, available from  Many of the tools don’t do anything useful without elevated root privileges as in a rooted Android device.

Many Android applications that require root privileges use BusyBox from the command-line extensively. Some of the utilities are powerful enough to severely alter your device, such as the ability to write data directly any partition on your device. Many third-party firmware packages including Cyanogenmod utilize BusyBox extensively and already come with prebuilt with it, so users should be aware of consequences if making any modifications to the existing installation of BusyBox, by themselves of from one of many pre-packaged Play Store applications.

Keeping it on your device usually isn’t going to be a problem, but keep in mind that this tool can be destructive for your device and can make your device open to vulnerabilities compared to a stock shipping device. If you use the command-line a lot, you probably know what it is already and want to keep it installed.