Desarrollo de App Ios, Android & Web

We need an application for Web (with PHP) and Mobile (iOS and Android) that works as a small social network where users can join challenges (created by admin only), pay a fee and if they win that challenge, split the pot between winners. Through the challenge, users can interact with others posting messages and responding to others. Functionalities include: > Pay entry fee via Paypal > Upload photos that proves the complete of the challenges (this photos will only ve reviewed by referees in admin portal) > Track Kilometers that a user runs day by day during the challenge (they need to click on a button to start their workout and click again to save that workout do the app know when to start/stop tracking). This needs to be done not by GPS but Accelerometer/Pedometer inside the phone so users can run on a treadmill. > Admins should be able to send custom notifications to users The website should include both user end and admin section so Admins can create new challenges, send notifications, release payments to winners and review status of each user. Mobile apps are only for users. We think a framework like CakePHP should help us in doing this fast (which is needed) so if you want to do this, go ahead. We are going to give you guys the whole design of the app in every format so you can focus in development.