Twilio Invite System on iOS app

I need the Twilio-based invite system re-integrated into my iOS application. This feature was previously part of the app but was removed. Your task is to reintegrate this functionality/screens and troubleshoot any related issues that may have arisen since its removal.

Key Language & Frameworks:
- Objective C
- Native App & UIKit

Potential Additional Work:
- API integration
- Core PHP website modifications

I can provide the original specification document for the invite system if required.