There is a great deal of information, and misinformation, floating around about how to maximize battery life on your Android device. We at Samsung Update decided to try to distill information from reliable sources
into a single post that can serve as a reference. This particular write-up is based on the Samsung Galaxy S3, but should be applicable to any Samsung phone (and any Android device). A few general comments before we begin:
These tips are generally accepted or documented to be accurate. If you have reason to think something is wrong, or that we've missed something, let us know. If you can provide evidence, we're happy to revise this. We don't claim infallibility.
We've divided these tips up into several posts: This post, and part II of the series, includes tips that don't compromise functionality significantly. Other posts will includes tips that will increase battery life at the expense of some functionality, as well as some internet myths that don't work at all or cause more problems than they solve. Also note that none of these tips require rooting your phone. There are other things you can do with a rooted device, but that's a topic for another day.
So, to kick it off: Battery life is mostly affected by the Big Three: Signal Strength, Radio Usage, and Screen Brightness / On Time.
Almost everything else is nibbling around the edges, so let's look at those first. It might seem that we'd start with Android's Power Saving feature, but for various reasons we'll cover that later.
There isn’t a whole lot you can do about this, other than move to another location, but a weak signal causes the phone to amp up the gain (amplification to the radio) which plain and simple eats power. With a strong cellular signal and strong WiFi, I might get a good 16 or more hours of light
usage on the OEM
battery. At work, this author has strong WiFi, but weak cellular. Even with WiFi in use for data, I’ll get at best about 12 hours of light use. Turn off WiFi, and rely on that weak cellular signal for data, and that might drop to 6 or 8 hours. Life in a weak signal area sucks: complain to your carrier, buy an extra battery, switch carriers, or move.
Things you can do that have relatively low impact to phone functionality
Turn radios off when you’re not using them
Radios use some power even when not actively being used. Read on for specifics
WiFi is better than 3G which is better than 4G, except when it's not!
In general, using WiFi for data will use less power than using the cellular radio. But, signal strength plays a big role. A very weak WiFi signal may, in fact, force the phone to use more power than a strong cellular signal. 3G generally uses less power than 4G. But if you're downloading a lot of data, a 3G connection will take much longer to complete the download than 4G, and that uses more power. In general, I find the speed advantage of 4G worth the extra power drain, but if you're really worried about running low you could switch to 3G.
Consider using VOIP if you’re in a weak cellular area but have strong WiFi
T-Mobile offers this service, and Sprint is beginning to on some phone. If it's not available from your carrier, a program like GrooVe IP will let you make and receive calls over WiFi. You can turn on Airplane mode, turn WiFi back on, and get and make calls, receive emails, surf the web, etc. without ever connecting to the weak, power-draining cellular connection. Drawback: no SMS or MMS, which rely on the cellular network. I believe there are apps
that claim to allow texting over WiFi, or via email, but I haven’t tried any.
If you have a good WiFi connection, set “Keep Wi-Fi on during sleep” to Always
Go to Settings /Wi-Fi / Menu / Advanced and make sure this is set. If you have weak WiFi, you might want to set it to “Only when plugged in.”
Turn WiFi off when you don’t have a WiFi connection to use
If WiFi is on, and not connected, the device will scan pretty much continuously looking for a connection. This will use up your battery.
Turn off Sprint’s Connection Optimizer (If you're on Sprint)
Connection optimizer sounds like a great idea: use the more efficient, faster WiFi connection when it’s available. The problem is that this has the phone searching for WiFi even when it doesn’t exist, which eats battery. And since most of the Wifi connections it does find are private, you can’t connect to them anyway.
Turn Bluetooth off when not in use
This doesn’t seem to use nearly as much battery as WiFi, but it will scan for connections periodically, which will use some battery. If you're not using it, turning BT off will help a little.
What about GPS?
This isn’t quite as clear cut as it used to be. From Ice Cream Sandwitch
forward, turning the GPS radio on in settings doesn’t mean the GPS radio is on all the time. The OS now controls this pretty effectively, and only turns the GPS radio on when an application is requesting location services. Controlling those applications is more important than turning the GPS radio itself off, but if you want absolutely maximum battery life turning GPS off, and preventing programs from using it for location services will help. USING the GPS for navigation will use lots of battery, however, so if you’re using your phone as a GPS in your car, invest in a car charger.
What about NFC?
The Android implementation of NFC
is pretty smart. If the screen is off, the NFC
radio is off. If the screen is on but locked, NFC
is on but not actively polling for connections. But if you keep the screen on a lot, you might want to turn the NFC
Turning these radios on and off all the time is a pain in the ****. Isn’t there a better way?
Since you asked, yes. If you have a Samsung phone, you can use TecTiles to easily switch various radios (and other settings) on and off when you get home, get to work, are in your car, etc. Alternately, use a profile manager that can turn various radios on and off depending on your location or other conditions. Here’s an example: I have a home profile that turns off Bluetooth and turns on WiFi (and more, but we’re just talking radios right now). When I leave the house, it switches to a default profile that turns BT
on and WiFi off. At work, WiFi gets turned back on, and BT
I use an app called Setting Profiles, which works well for the most part, but seems to be unsupported these days. The free version will do almost everything the pay version does. Another program is Llama, which many people seem to like but I’ve not used. Tasker is the King Kong of profile apps
, and will control things nothing else will, but the user interface is awful, the program complex, and the learning curve steep. There are several other profile apps available in the Play Store that I've also not tried.
See Part II
of this series, coming soon, for more tips and tricks
related to battery life.