Hey'
What kind of approach we will be having :
We would like to kick off with Android version first , get it done and get it approved from you as well. Once its done we would move on ios side and our Android team will transfer knowledge ( KT ) to them , it will save time and efforts.
The second Approach would be deploying one dedicated resources on Hourly basis ( its our recommendation ) , by doing this he would be holy Solly responsible to wind it up successfully he can take one shadow resources with him to work on small task ( UI and Apis implementation ) that will help to cut down the time.
The third and last approach would be to put everything on Asana ( Project management tool) or Create a list on Google Drive to give regular update to you. that will make our team responsible it will put some pressure to our team , dealing with client directly create a good atmosphere.
Thanks and Regards
Shiv