In North America Plugshare is by far the preferred solution.
There are dozens of apps that try to do this, but as every one of them counts on people manually entering the information, there's no point in even bothering with anything but the biggest one out there, which is Plugshare. Doesn't matter what other features they tout, if they don't have the same volume of users as Plugshare they simply won't have the same number of chargers listed.