Correct bugs in ios app

I need an ios (apple) apps expert's cast on my already build and published app to correct bugs here the functionalities to fix. the source code is available. I can run through the details of the app with the successful candidate, but in a nutshell the app is for a rota system, workers get notifications of job posted, they can accept, clocking by scanning the QR code, and get directions. here are where the bugs are to be fixed: - the accept button must send notifications back to the server - the app must receive notifications from jobs posted - user must be able to clocking/out - live direction button must also work.
the successful candidate must update the source code and test and send back to us. Please note a full api is available if required, but I believe only a few syntaxes need fixing on the code as all has already been coded. We can discuss futher.