If you’re constantly switching between a cellular data and a WiFi connection, having both enabled results in faster battery drain. Having a rooted device makes it possible to automatically disable cellular data when connected to WiFi on Android.
As long as you have a reliable WiFi connection, you most definitely don’t need to have cellular data enabled as well, but it can be annoying to manually switch it off all the time.
A root app called RadioControl will automatically disable cellular data when connected to WiFi. First, the app enables Airplane Mode as soon as you connect to a WiFi network, and it disables it when you get out of range. This practically kills the cellular connection exactly when you don’t need it, and helps you save a decent chunk of battery life.
How to automatically disable cellular data when connected to WiFi on Android
Before we proceed to the instructions, you should know that in order to install RadioControl you will need a rooted device running Android 5.0 or higher.
You can download the app by visiting the link below, or by simply searching for its name in the Play Store app.
At first run, the app requires Superuser access and you will need to grant it. Then, you will have to go through a quick setup guide.
After you complete it, go to RadioControl’s main menu and toggle its service on. Now you should tweak the app’s options, so tap on Settings in the side menu.
Now, tap on ‘Network Settings’ and you can select any WiFi connection that you’d want to blacklist, meaning the app will not kill your cellular data while you’re connected to that specific hotspot.
Many carriers offer Wi-Fi Calling, and enabling this option can be useful since without the cellular data connection you might not be able to receive and make phone calls. If you want to enable Wi-Fi Calling (assuming your carrier supports it), head over to Settings -> Wi-Fi calling, select ‘Wi-Fi Calling’, enable it and set it to ‘Wi-Fi preferred’.