Show power level next to bluetooth icon
For certain devices (like e.g a headset) it would be very helpful if next to the bluetooth icon is a charging meter showing the current charging level. It is very annoying when you are in the middle of a call an suddenly your headset has no power anymore.
When the same headset is connected to my mobile phone then I can see in my mobile phone how much power is left and I can charge the headset a few minutes before a call if needed.