Anki is wonderful; I've been using it for a while. One nice feature of Anki is that it can sync between the web, desktop and mobile versions of the app.
Maybe this would work for you.
Your reply did make me take another crack at it and I got it to work. The script if anyone is interested: http://pastebin.com/pC9VTzjv. It does do some specific-to-me things to close apps I usually have open that did not want to minimise.
In either case, it isn't nice as an individual to be singled out as a target for extra cash because of the platform you run on. Just because I use an iPhone doesn't mean I have more money than my peers (and in fact probably means I have less!). Even if that were true on aggregate, I still find it unpleasant, simply because there will be many exceptions.
Assuming the iPhone is yours, sure it does; at least, more money than a student who can't afford £17 for a learning tool. The iPhone itself is an asset that is worth money.
The iOS app is the sole source of income for Damien, who develops, hosts and supports the entire Anki ecosystem for free. At some point a few years ago, Anki was taking up so much of his time that he had to decide whether to quit his job or stop developing it. He chose to quit his job and make a paid iOS app.
I think £17.50 is a reasonable price for such a complex app. Many people who own it use it for over an hour a day. If you think of it as less than ten cups of coffee, and consider that you would pay much more for a textbook, I think it's a good value investment for the educational return you get.
If you really really cannot afford £17.50, you could always join the beta program next time there's a call for testers on the user group, or you can use the web version on your phone.
With regards to how you arrive at the $200 figure: for you, Anki is competing against "$1000+ for with traditional modes of learning", and so you feel it's worth up to $200. Well, it's also possible to frame it the opposite way, because for me Anki is competing against traditional (free) libraries and a $1 stack of flashcards, in which case it seems way overpriced to me. So I don't think that's a compelling argument either way.
Could yourself and Damien not make an equal amount of money from the iOS port by having a cheaper app and making up for it in volume? I appreciate support costs do not scale trivially in a case like that, but is that something you've thought about or explored? If the price is a gesture against the app store's 'race to the bottom', then that's admirable, but this just seems like too far – especially considering the audience for your app (in my opinion).
With regards to:
> If you really really cannot afford £17.50 ...
That could be fine for me, reading your comment, but not for most of the people priced out of the app. I personally just switched to a lower priced app, like this one: http://apps.chbeer.de/ivocabulary/ (full unlock is £3, and it has a very fine legacy having been derived from the ProVoc codebase, I believe)
Regardless, whether it's intended that way or not (and I suspect not), it feels like I'm being punished for using an Apple product because the price of your iOS app is so different from every other platform, and that isn't a nice feeling.
We discussed the complexity issue with existing Anki users and they don't fid it complex - but people who aren't already using Anki do. By setting the price higher, volume of sales is sacrificed in preference of selling to people who understand what they are buying.
If people want to buy the cheaper app, that's OK. Some of them are great apps (nowhere near Anki imho, but I'm biased :). We hope that people who derive real value from using Anki every day will understand that the price is a way for them to support the whole Anki ecosystem.
Sure, you're comparing the price to free on desktop, but I suspect you're also somewhat comparing it to typical app store prices. We've been educated that software for our mobile devices costs a nominal fee.