I'm building an app that forms a network using Bluetooth. However, Android versions less than 4.4 do not support infinite Bluetooth visibility duration. Every x amount of time (usually an hour), the app has to prompt the user to enable Bluetooth visibility. In 4.4, you can go into the Bluetooth settings and select "Never timeout" for Bluetooth visibility.
What changed between Android 4.3 and 4.4? Why didn't Android 4.3 support infinite visibility? Why does 4.4 and higher support infinite visibility now?