Developing on going app ( already exists )

?* ONLY for freelancer in Saudi Arabia *?

Developing on going app ( already exists) two IOS app + 2 android .
Native android and iOS app:
Java for android
Swift 5 for iOS
Php(ci) with MySQL database for backend.

What we looking for Most important thing a developer that speaks Arabic to do the following :
1 - re-design the front-end to comply with a Middle East region (specially Saudi Arabia )
2- go thru the existed back-end and fix some bugs .
3- the apps need generally to be simplified make it quick and easy use like ( Jahez ) app .
4- the apps already has schedule and time functional that needs to be re-design to be similar to ( my table ) app.
5- time is a big factor to us .