I bought this for my husband for Christmas and he loves it!  He would always forget to charge his phone or his ipad until we were on the road somewhere.  Now he can charge it anywhere.  We haven't had to use it too often yet, he's only used it to charge his phone once so far, but that time it worked great. We don't know how well the bag itself will hold a charge, but it's a fantastic idea and seems very easy to use.