Management by abdication can be a major risk. Instead of outsourced, think of your team as a distributed team location wise. From there figure it how you can participate in all aspects of it, if you are hands off you will spend much more fixing it over and over.
Development for an app between 500-2000 seems low and a way to hook someone in for more. Depends on how simple your app is I guess.
In terms of platform whether you outsource or be heavily invoked with a remote team, I think flutter has a lot to offer especially since it’s one of the best at making one codebase work on android and iOS instead of building separate apps which is not ideal especially with a limited budget.
Good luck
Mandatory to follow. Just thinking about it makes me want to check everything again