Aaron has updated his Samsung Galaxy S3 and now his battery life has decreased. Leo says it may just be that the phone is older and the battery has diminished some. The phone isn't old enough to have battery life issues, though. So it's likely that there is a bug in the update that's causing some programs to run in the background. Doctor Mom in the chatroom had the same problems and suggests turning on power saving mode in Android.
Rafael's phone dies while he still has battery life remaining. Leo says that the phone guesses how much battery life remains and often it's an inaccurate guess. So it should be taken with a grain of salt. It may have just crashed, though. Leo says to charge the phone all the way up and then run it down until it shuts down. Do this several times and he will essentially "teach" his phone how long its battery life is.
It may also be a defective phone. Leo advises documenting his experience with it, and taking it to the Apple Store.
Eric has a Samsung Galaxy SII and he's not happy with the battery life. Leo says that is a common issue with today's smartphones and Leo always just buys a backup battery. There's a few things he can do, though. There are tips at XDA Developers Forums. Search for battery life and he'll find some great advice.
Damian is 10 and has an iPhone 4S, but the battery dies in about 3 hours. Leo says that's largely because Damian plays with it a lot. He also noticed that the phone crashes after overheating. Could there be something wrong with it? Leo says there probably is. He advises taking it to the Apple Store. They'll replace it if it's still under warranty. To preserve the battery life, he should turn down the brightness, turn off bluetooth, and check email manually.
Turning off extra services like Bluetooth can help. If he has 4G turned on, that'll really eat up the battery. So if LTE isn't available in his area, it's a good idea to shut that off. Leo also suggests backing up the Android phone and performing a factory reset, which often fixes issues. Leo also suggests getting an extra battery for his phone. Or if battery life is really important, the Droid Razr Maxx HD has the best battery life on the market.