PingPal.
Opensource. Backend-as-a-Service Shootout (the best alternatives to Parse?) Using a Backend-as-a-Service (BaaS) can reduce development cost and time-to-market.
It’s a simple way of getting a highly scalable backend solution without significant upfront investment. This avoids the technical risks of having to scale your own service to meet demand as your user base grows; in a world where an app that hits the store top charts might gain more than a million new users before you complete your next iteration of development this is worthy of serious consideration. In most cases the tradeoff is giving up control of your backend. This tradeoff was brought into the spotlight recently when the most popular BaaS, Parse, was acquired by Facebook.