This simple app can help you increase the standby time of your device: WiFi Automatic automatically disable your WiFi radio when you don't need it and thereby lowers the battery consumption.
You can also specify to automatically turn on WiFi again, if you turn on your device or when you enter a specified location. Also, the app can regularly scan for available networks to connect to and re-disable WiFi if no suitable network is found. This way, you are always connected to your WiFi network when using the device.
WiFi Automatic is open source: https://github.com/j4velin/WiFi-Automatic
1.5: turn WiFi on at specified locations
1.4.9: changed some option titles to better fit on small screens
1.4.8: fixed issue with "turn off WiFi if screen is off" on some devices
1.4.7: minor improvements + Russian translation
- disabled UnlockReceiver when the "turn on when unlocking" feature is not used
- target SDK updated to 5.0
- theme changed to Material