have an old Motorola Razr with mini USB charge port, no apps but for charging... my Goal Zero 7w panel to charge my Guide 10 battery pack (4 Sanyo AA Eneloops) which has a charge cord from USB to miniUSB... the Guide 10 pack is stand alone for approx 2 charges.. 12vdc tubular charger in car... back up is my Garmin GPS which also uses mini USB via 12v tubular