This may have already been addressed elsewhere but, save for the fake amazon.com hijack ads, there are two "features" that makes FT on mobile nearly unusable for me.
First, I use a 5" phone and I have no desire to go to a phablet. Quite often I have to pinch zoom in to read something and when I do, the right-justified ad bar "tears" away from the right side and fills the middle of the screen making it nearly impossible to read or edit.
Second, when editing a post, when I place the cursor in the text box the text that I am writing pops up and under the edit control box where it can't be seen as I am typing.