Online test conducting system needed - Branded apps as well for IOS and Android

Hello

We are an institute looking to conduct test series online.

What we are looking for

Ability to add test and manage users and results in admin panel which works form PC
Front end website for students to take tests
Android app for students to take tests
IOS App for students to take tests
personalized branding

We are open to template solutions as we don't have a lot of budget.

Please propose the best quote you can get this all done for.

Thank you