Having studied a foreign language (Brazilian Portuguese) as an adult, my experience is that learning written and spoken language are separate skills. Just because you know a written word doesn't mean that you will recognize it when it is spoken.
My experience is that I had to learn every word twice: once as text and again as audio.
This was despite the fact that Brazilian Portuguese is much more regular than English in mapping sounds to letters.
Quizlet and similar ideas look fine for written vocabulary, and helping you read, but don't kid yourself: you're not going to be able to listen and speak by mastering this tool.
Having been in the same boat as user 'computador', I second what was said. As an American who has lived in Brazil and Portugal, though, even getting the spoken component down does not always mean full comprehension (as I found out in Portugal). I find myself, sadly, glazing over when Continental Portuguese is spoken because it seems like one long, run-on sentence, spoken inward (if that makes sense, as opposed to Brazilian Portuguese which is spoken outward). It's rather frustrating to be fluent in Brazil (in all ways that matter) but handicapped in Portugal.
If it makes you feel better, spoken Continental Portuguese can be somewhat hard to understand even for us Brazilians. Roughly speaking, it's like the difference between a Southern US accent and a (non-RP) British or Scottish accent.
Although, to be fair, Brazilian dialects too vary a lot in terms of pronunciation.
The language we're talking about makes a big difference here. I have (very) occasionally been mistaken for a native Japanese speaker over the phone, but I have the reading level of a 12 year old at best.
That's a great point, listening and speaking is much harder than just being able to read and match some words.
We did consider using text-to-speech to say the word out loud once you answer it, but it wouldn't be ideal to have to hear every time you wanted to unlock your phone.
written and spoken are quite different at the point of understanding, but mastering written language implies understanding grammar and vocabulary, and that does help with speak too (modulo tolerable pronounciation).
What I mean is, in an absolutely personal opinion/experience:
I still have big troubles understanding spoken hungarian in contrast to written, although pronunciation matches written almost 1:1 I just can't tell the difference between ü u ú Ű) etc.. but at least I can sort of express myself, even if I do it by mispronouncing most words.
So, written does not imply spoken, but it does help.
Not to mention this has no capability for helping you learn grammar or verb conjugations etc... ie. the stuff you'll need to know in order to write OR speak in sentences. Still pretty neat idea for studying vocab, but nothing more.
The UI is a bit heavy here and with 4 words to choose from, even without knowing much about the language it is pretty obvious what the correct answer is.
What a great use of attention. Someone needs to integrate this with anki.
Although making sentences relevant to the learner is also a big part of language learning, and the FB part does help there. It's almost killing two birds with one stone.
I really like the idea of using the lock screen as more than just a simple way to get into the phone. I would love to use something like this to force me to spend a few seconds learning something every time I want to get into my phone.
I recently installed DashClock https://play.google.com/store/apps/details?id=net.nurik.roma... and while it's not strictly a 'learning' tool you could likely write an extension for it to do what you are looking for. I like it so far, better than normal lock screen anyway.
Has anyone noticed they're showing the Portuguese flag instead of the Spanish one on the opening page? (I do prefer the Portuguese flag, but I would have thought they would get this kind of thing right..)
My experience is that I had to learn every word twice: once as text and again as audio.
This was despite the fact that Brazilian Portuguese is much more regular than English in mapping sounds to letters.
Quizlet and similar ideas look fine for written vocabulary, and helping you read, but don't kid yourself: you're not going to be able to listen and speak by mastering this tool.