Save battery life by handling your wifi smart.
Wifi timer: the wifi will be turned on for half a minute in the interval you set, so you can save battery life.
Wifi screen: every time you turn your screen on, wifi will be turned on, and when you turn your screen off, wifi will go to sleep in maximum 2 minutes.
CHANGE_WIFI_STATE,ACCESS_WIFI_STATE : to check, and modifiy the wifi
RECEIVE_BOOT_COMPLETED: to make sure, the app runs after reboot if it was running before
WAKE_LOCK: if the timer is enabled,the app keeps the phone alive for 30 seconds to enable wifi and let apps use it
READ_PHONE_STATE: won't change wifi state if there is an active call
source code: https://github.com/2ma/WifiSaver
2.1: fixed small bug,different icon, new number picker, made source code public
2.0: redesign, widget added