Okay, before I start, a quick note; This does not allow you to use any of the latest features because the method used restores and older version of the app.
iPad (Not iPhone, because the old editor was never on iPhone)
Your mac computer must have been synced with your iPad when it had the old version of the app.
WARNING As thin buffalo stated, this could be risky, and you should backup your projects before trying.
Here is the link to the website with the guide.