Since iOS7 it seems that when a TIWMemo component is near the bottom of the screen, the Safari iPhone keyboard covers the memo when running in fullscreen, instead of pushing the screen up so you can still see the memo whilst typing. If I use the previous and next keys on the keyboard to move to another text box and back to the memo again it behaves properly after that.
You can replicate this by dropping an TIWIPhoneStyle on a form and setting to Fullscreen.
Add a TIWMemo component near the bottom of a TIWIPhoneRegion and run in fullscreen.
I have tried 7.04 but it makes no difference.
I am on IW 12.2.20 and the latest iPhone controls set.