Have you considered setting up an agent environment like codex and having it work making on Android version for you? I know you said it's a very complex app and that probably makes it seem like it wouldn't be able to, but LLMs are really good when they have a very clearly defined end state to work toward, like an existing iOS app with code, screenshots etc.

I bet if you set Astra codex against this task on the $100 plan it would have it done at a speed that would shock you. Potentially even by the end of the day and mostly uninterrupted.

The SOTA models can reverse engineer whole codebases even from assembly now. If you have to specify with words what you want to do it's still hard but if you have a codebase to work from, you can pretty much arbitrarily convert apps and games into other languages / platforms now as if by transitive property.