The big flaw here is the price, which is outrageous. Its over 20 times (!) the average price of an AppStore app, and double (!) the price of even the most professional apps from Apple.
Its also buggy, jumpy and rather slow. I tried to start a document by pasting some text in from a text file and even after saving in final draft format, it then refused to open the file ever again. Moving around in files is jerky and slow. If you have any screenplays already, YOU WILL HAVE TO RETYPE THEM IN BY HAND! Outrageous.
Its basically a port of the original Final Draft desktop software to the iPad but given what it is, and given the other apps in the store, its really the kind of thing that should cost about $10.00, but instead you will pay $40.00.
The worst thing of all is that it doesnt seem to integrate into iOS very well in that it doesnt use the system dictionary for spell check and a few other details. It doesnt however give you access to whatever dictionary it is using so if, like me, you write in English, every second word will be highlighted as "incorrect" even though Im writing on an iPad localised to Canada and using the built in UK dictionary. This is just lazy and INSULTING to the end user.
Lastly, like many apps, it wont sync your documents unless you use the unsafe, insecure American "DropBox" service instead of iCloud so NONE OF YOUR DOCUMENTS ARE SAVED!
Horrible, snotty, American only app.
I guess an aspiring screenwriter could take this as their first lesson about Hollywood.
You *will* be ripped off! :-)
Jeremy Bee about Final Draft Mobile, v1.1