I really love this app, and consider it well worth the money spent on it, especially considering how powerful the desktop software is, and how well the two work in tandem. It does seem like there should be an intuitive way to download shared decks to the Anki Mobile account from within the app, rather than having to go to the site externally.
There is however a reoccuring bug that bothers me about once or twice a week: a question appears, to which I answer "good", and then the next question appears. After I answer that one, the first question (to which I answer "good") re-appears! Sometimes when it reappears, it just shows me the answer half. Occasionally, two different cards will alternate like this, and Ill just see those same two cards for the remaining ten or more cards I have left to study; this is definitely a bug, and Im sure others have seen this behavior. Im not sure if it is disrupting my statistics.
The price of the app is more expensive than others, but a real bargain considering the effort and value it offers; I have easily spent more time using this app than any other Ive purchased (mostly to review Japanese kanji), sometimes a couple of hours a day.
My favorite thing about the app is that I can use it almost anywhere, for thirty seconds or thirty minutes or whenever. With a bit of tuning, the app does exactly what I want without any troubles (except the bug I mentioned). If I get interrupted or have to step off the train, I can pick up exactly where I left off; the interface is snappy and quick.
After using this app daily for several weeks, my retention scores for kanji have gone over 95%, and I couldnt imagine not having this app; it is easily my most used iPhone software. The documentation can be frustrating at first, and it really needs to be rewritten and simplified, as it seems other reviewers have had trouble. I remember it took me longer than it should to get set up; maybe I should write a tutorial?