Hello,
I’ve gone through your requirements in detail and can help you to customize the app launcher into a Gridview. I've more than 10 years of experience with native Android app development and glad to inform you that I’ve expertise in working with similar jobs.
However, before providing an accurate timeline & cost, I would like to connect with you over a chat or call for further discussion.
Let me know a time that works best for you!
Regards,