Hi Kirill,
I didn’t see Arjan or others with App experience chime in yet, so here are my 2 cents :)
I think you can use any kind of client-side framework and call API methods to get your data.
A choice you can make is to, either:
1. use API data and render on the client; or
2. render snippets of HTML on the server and do composition in the App.
I think that Arjan and others are currently following strategy (1).
That is also what fits most App frameworks.
On a side note, we are working on new front end technology that will be more App (or Single Page App) friendly.
We are following strategy (2) with this new technology.
You can see the work in progress here:
And here:
Realistically, we should have Cotonic/Zotonic stable by the summer.
Cheers, Marc