Android APP bug fix and enhance ,This APP is already Developed , its very small app

This APP is already Developed , its very small app below functionality

1) Login using phonenumber , google auth -Firebase
2) User is able to take photo and upload -Upload Image using a rest API and get results from API show to user .

**I need help you to do a Proper testing of this app fix bugs if any . once you are done with testing at your side i will be testing ,
***IF need we might enhance the specks with very small scope .
And Fix if we get the bugs .

Also i have to golive and if i need help in worst case i will reach out to you for help .

This is a very small app i don't expect any high costing implementer ,Also be very clear on the requirement posted .I need this to be completed max few hours /2 days at last .