so if you exceed a certain amount of text, that comes quickly as soon as the keyboard pops up, you must scroll to see the icons and then you loose sight of the current insertion point where you want to add something. The typical or the worse one is emoticon. Once you hit that icon, you have most of your screen occupied by keyboard down and the emoticons up. When you pick one, you can't see if it has been inserted or not. So if you called or hit the wrong one, you must go back up and repeat the action.
An example below: