We’ve all been there. You’ve been out all day and suddenly that low battery alert pops up on your phone.

If you’re lucky, the bar you’re at might have the right charger for your phone behind the counter. If you’re not, you’re walking or taking the bus instead of calling a car service.

But with Y Combinator-backed Doblet, you might be able to get a charge even when you don’t have an outlet. The startup is putting portable batteries that charge Android and iPhone 5 phones in bars, restaurants and coffee shops. Users have the option of paying either $3 for a single charge or $30 for an annual subscription to the service and unlimited charges.

Read the full story on TechCrunch