I've noticed on iOS 9.0, 9.0.1, and 9.0.2 that the bluetooth indicator on my 6S randomly disappears and reappears. Sometimes it will not show on the lock screen, but once unlocked it appears in the menu bar. Other times it won't show up at all unless I toggle bluetooth off and back on in the settings. Is this an iOS 9 thing? I haven't had time to test if the bluetooth connection itself is actually flaking out. It's doing this when there is nothing connected via bluetooth, but bluetooth is on.