Make android app that communicates with Home assistant

There is a open source automation tool that is called Home assistant. I would like to get this app with my own logo etc. That communicates with the local home assistant hardware. For documentation on how to do this is also open and readable in de following link.
https://developers.home-assistant.io/docs/api/native-app-integration

I just need a mobile app developer that wants to work with me for a long term.
If possible we want to android app and also a iOS app.