Swift iOS App refactor, API & database optimization and security

I need someone to do a few tasks for my company and our mobile application on Swift iOS. First, you have to optimize our Python API and add industry-standard security measures to it to prevent hacking or request overloads. Secondly, you have to refactor and optimize the integration of this API into our swift app so the connection is flawless and leads to no timeouts. Finally, refactor the rest of the Swift code to app-store readiness.