The device delivers what it promises. I can therefore fully recharge my i-Phone comfortably once. However, I have the charger always charged at the socket. A disadvantage of this solar charger is that the charging by the sun just takes too long. Because maybe you really have to use the Solar backpack ET-2 in addition, so that the charging is faster. Conclusion: Top device on the go. But you should not rely solely on the solar charging itself.