I've been testing the closed beta for a while and to be honest i'm not all that impressed, it seems like a more limited version of Anki so far. I thought that's because it's just a beta version, but the e-mail i received says that it is "market-ready":
It is with great pleasure that we announce the release of our Official Beta. After months of development, refinement, and testing, we are proud to release a market-ready language-learning app that brings our revolutionary method to life.
I suppose it'd be ok if you were an absolute beginner, but they're not offering any languages that i'm an absolute beginner in and all of the word choices are way too easy. Some of the sentences are more interesting (though a lot of them still seem a bit awkward to me), but you still have to learn a word you already know to get access to those sentences.
As for the UI, it looks nice but it's not all that practical, again if you're an absolute beginner it's probably less of an issue, but having to swipe through tons of words i already know in order to skip them is boring, annoying, and time consuming. The same with the actual review section, having to swipe left or right looks pretty but i'd rather just hit a button, as it is it sometimes doesn't recognize my swipe the first time.
Currently i couldn't imagine using the app as my main source of study, i'm having trouble staying motivated enough to use it as a supplement. For mining sentences/vocabulary, i think something like the Readlang plug-in is much more interesting.
Have any of you tested it out? I'd be curious to know your thoughts and if you have any ideas on how to use the app more successfully than i have been using it.