Rate the Android or iOS application/program you use most frequently. 
Can be anything. 
When using system built-in apps, please mention what firmware are you using. 
For me, it's either 
Neutron (while charging) or 
Poweramp (while on battery). 
Both of them are powerful, but Neutron gives better quality and a ton of more features and more control, for a price of higher battery consumption, which is highly visible. 
This is why I give them almost the same rating. 
89/100