Example mobile app

[reez]

Would like to do an example mobile app for this repo. We do the same for Swift and Kotlin.

Let's discuss what features we'd want in a first version of this, I'd like to keep the feature set simple at first (send, receive, explora, etc), and definitely want it to feel nice to use.

[Johnosezele]

I think a good place to start will be reproducing the features we have in the Swift and Kotlin ones as we build upon them and also catch flutter related issues. I shall open a draft pr this week.