Subscription based mobile app help -- 2

I'm building a subscription-based app using Ionic React on the frontend and Slim 4 (PHP) with MySQL on the backend. I need a developer to help implement secure authentication, subscription validation, and enterprise access, with support for offline use.

What I Need:

Authentication

Secure login/logout system

Sign-up and password management

JWT-based session management (or similar)

Store auth/session securely on the device for offline use

Subscription Validation

Validate subscriptions (individual and enterprise)

Persist access data locally so users can access features offline

Sync subscription status with backend when online

Enterprise Accounts

Companies can create a master account

Company accounts can invite/add multiple users

Option to invite users via email or access code

Backend Integration

Slim 4 backend using MySQL

You’ll help build or connect endpoints for login, token generation, subscription checks, etc.

Tech Stack

Frontend: Ionic React

Backend: Slim 4 (PHP)

Database: MySQL (via MAMP during development)

Deliverables

Fully working authentication system

Local storage of access/session data for offline use

Subscription checks with both individual and enterprise support

Backend endpoints (if needed)

Basic security best practices

Ideal Developer

Experience with authentication flows (especially offline-capable apps)

Comfortable with Slim 4 / PHP / MySQL

Can suggest and implement secure offline-first strategies

Clear communicator who can collaborate and explain architecture choices

I would also consider using a service like RevenueCat or a similar solution and have someone set it up for my app.