Android: From hard-won experience, we've previously labelled android app APNdroid as a crucial battery-saving utility. With faster operation, an automating plug-in for Locale, and the ability to keep MMS messages coming through, it's even more essential.
On its face, APNdroid doesn't do anything fancy, and, in fact, is kind of weird: it turns off your mobile data (EDGE/3G) usage by messing with your Access Point Names (APN), leaving you with the basic voice call/SMS capabilities of a standard mobile phone. But if you're rocking an Android phone with annoyingly limited battery life, this feature can be a real battery saver for stretches of time when you're not going to be tinkering on the web or checking email.
Previously, APNdroid took a good 4-6 seconds to do its thing, and locked up your phone while doing so, as well as denying picture messages over MMS. The 2.0 release, now available in the Android Market, offers a home screen widget that turns your mobile data on or off in about a second. If you're using the very awesome Locale app to automate your phone based on location, time, battery state or other conditions, APNdroid now offers a plug-in that can turn off mobile data when, say, you hit 20 per cent battery life, or maybe when you're going to sleep most weeknights.
APNdroid is a free download for Android phones only. Need to get even more juice out of your Android phone? Check out the relevant section in our exhaustive guide to saving a smartphone battery.
APNdroid [Google Code]