Hello 
This is a really nice job! I love it. 
It feels like a much more modern and elegant way to compose. I also tried moving the toolbar to the bottom in the past, and I think it’s much more comfortable this way.
Overall, it looks pretty clean. One thing I noticed: when the title recedes and the body gets focus, it might be a bit confusing how to bring the title, category, etc., section back into view. Since the whole composer textarea is swipeable this case, I think adding a visual grip/handle could help indicate this to users.
