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This is intentional. Apple designs simultaneously for the Luddites and the tech savvy, because those two extremes are their target audience. My boss at the sheriff's office is a technological neophyte (despite, ironically enough, being in charge of a data processing department) yet within a day of owning an iPad mini she had the majority of its functionality down.
When I briefly had an iPad (now owned by my fiancée) I was using it to ssh into my home server, create real music with GarageBand, and write parts of my novel with a $5 app that rivaled the excellent Scrivener for Mac.
My point being, it was just as easy for my clueless boss to pick up and use as it was for me, a ravenous consumer of all things tech. That's the beauty of Apple's design philosophy and also the source of a lot of the ridicule they suffer: Nearly anyone can pick up an Apple product and figure it out within minutes.
It's called My Writing Spot. It doesn't have all of the advanced features of Scrivener, but it is by far the best mobile writing app I've used. Anything I wrote with it, I would sync into Scrivener when I got home in one step.