Development of API for existing database order system - repost

Project reposted as freelancer awarded has been removed from Freelancer. We currently have a MYSQL database and simple PHP admin backed for receiving and sorting orders placed with an iphone app. We require an API developed for a specific external client to connect to us to send us orders and us to be able to connect and update their order status, etc. It involves a bot of PHP coding, some MYSQL database changes and such like. The API specs include: ● All calls operate with the Content-Type “application/json”. ● All calls should be HTTPS ● These calls do not include an auth scheme. ● There is a webhook that needs to be connected to for order updates to their server. Project is a fast-track and needs to be completed very quickly and cleanly. There is scope for some additional work to change other areas and updates to our iPhone app if the freelancer is also experienced in Xcode and iphone apps.