I just checked it out for a few minutes and signed up. It looks very nice (lots of attention to detail, I can tell). I'm a native English speaker actively learning Spanish, living in Buenos Aires since November. I'm at the point where vocabulary seems like a bottleneck for me, so readlang may be a good fit.

Since reading/vocab is just one part of language learning (in addition to grammar, speaking, listening, etc), it seems like Readlang could fill this gap that other tools have (verbling, duolingo, etc). See if you can get the attention of some other bloggers in the language learning community, like Benny (?) the Irish polyglot guy (fluentin3months), or even Tim Ferriss. If they blog about it, you'll probably get some good traffic.

I didn't see thai support . Any chance you will add that ?