It also come with a UBS adapter (though you can use detach the UBS cord from your phone charger and use it as well). The way it works is: You charger the "Go Lite" with your phone charger and it stores that energy and when you're ready to use it you just plug in you're phone and charge it like
normal. What I like to do is charge mine the night before and then in the morning just throw it in my purse and go.
I don't know about anyone else's "Go Lite" but mine didn't lose the energy it store even when I didn't use it for a whole week, so in my opinion it stores charged energy well. The only con I see with this and I don't know if' it's happened to anyone else, but when I DO charge mine phone sometimes I find that there's no juice left for a few more or even one other charge. Other than that, I really like it and I would rate it 4 stars. I say check it out and see what you think.