It’s a major bummer when I am caught out with a dead iPhone or iPad. That’s why I carry the Mophie Powerstationin my backpack. It’s smaller and lighter than my iPhone, yet can recharge it twice on one fill-up. It can also charge an iPad to about half a charge. I much prefer it to a case with a built in battery, because on most days the iPhone’s battery is good enough for me all by itself. It takes about an hour to charge an iPhone to 80%, but you can use your phone while it charges. It’s only $80 on Amazon.com, and it has lasted me through three iPhones and still looks and acts new. A great gift for a person on the go.