Posse is a Google-certified development agency. They're located in New York, New York and work remotely with anyone who needs a mobile app. Posse builds top-notch mobile apps that have reached top-ten standing in the Google play store. They build IOS/Android apps, server-side APIs, and wearables. They also assist with mobile design and strategy. They have a "no BS" strategy, which means that you won't get a lot of corporate speak and what-not there. Just mobile application that works. Their customers include Dewayne "The Rock" Johnson, Jet, and Gatorade. Since they're not a full-service agency, don't expect them to do anything but mobile-related applications and design.