Word of caution, just because your device is stable, doesn't mean you shouldn't update the OS. Most updates are more for closing security holes than features. Not sure about iOS, but for Android Google releases a monthly update specifically to close any security holes as soon as possible. Look up Blueborne. Effects basically every known Bluetooth device and allows a hacker to fully spy on you, even take pictures and video with your camera live, record audio from a smartwatch, and about anything else they can think of. IDK which OS version on Apple are effected, but pretty much every Android OS version prior to this latest security patch is effected.