Here’s create new topic (mobile keyboard not shown) on an iPhone 5:
Note than an iPhone 5 is a pretty small device these days, the iPhone 6 and 6+ (or 7 and 7+) are considerably larger.
With regards to the video. When you say “modal” what modal are you referring to? I’m not seeing bouncing? @jesscmc it looks like you explicitly chose to show the toolbar, which is not the default? Perhaps we should remove the toolbar option when creating a new topic @sam as there is no room for a toolbar on new topic specifically.
Another option, on new topic mobile, make the post content viewport considerably smaller, like 2-3 lines max. So there’s room for the keyboard to fit plus suggestions etc. Like so:
I am not sure how much people are going to type into a new topic on mobile but I suspect it can’t be much more than a few lines?