The Bluetooth Visibility Fix app can help you conserve battery life and enhance your privacy by automatically controlling your Bluetooth visibility settings.

When you connect to a device, the app automatically turns on Bluetooth visibility; when you disconnect, it turns it back off. This can help you conserve battery life and enhance your privacy by preventing your device from being visible to other devices when it is not necessary for it to be.

The app also gives you the option to limit Bluetooth visibility to known devices and to turn Bluetooth off automatically after a certain amount of time.

Get this from the Google Play Store.