When you enter an area where you can’t receive a cellular signal on your smartphone, the wireless radio on your phone basically serves no purpose other than to drain your battery. So whether you work in an office where you can’t get reception or you expect to take a trip through a part of the country where you can’t get any service, you might want to think about turning on Airplane mode to disable the wireless features of your phone.
Or you can just install NoBars for Google Android, which will do it automatically. NoBars detects when your signal drops to, well… no bars. At that point it can enable airplane mode. You can configure the free, ad-supported app to wait until you’ve been without a signal for 30 seconds, 2 minutes, or 5 minutes.
NoBars will also wake up periodically to check for a signal. If it finds one, airplane mode will be turned off indefinitely.
NoBars is available as a free download from the Android Market. By default, airplane mode will disable all cellular communications including 2G and 3G data as well as WiFi. But if you’re using Android 2.1 and up you can manually turn on WiFi in airplane mode.