When will we have a phone (Android/iPhone) apps on kBin? From what I understand developers are waiting for the API.

Artemis is a kbin mobile app in development but, as you say, the developer @hariette is waiting for the API to be deployed. Hopefully this will happen at the planned upgrade in a few days, which should help with uptake.

I'm writing this comment via Boost for Lemmy.

Kbin is federated, so - why not use one of the many Lemmy apps?