Cool to see more things like this. I'm a big user of Verbling - looks like this is supposed to be more structured? It's also more expensive

Verbling is awesome! Ours is a little different in that we recruit our professors, design the curriculum, and charge the same rate for each professor. Thanks for checking us out :)

Cool! Looking at the English instructors, it appears that the two you have are from the UK and South Africa. Although English was their first language according to their respective bios, my understanding is that people wanting to learn English place a premium on learning "American" English.

Perhaps consider bringing someone on board from the United States who has a non-regional dialect?

That's a great point and we are currently in the process of recruiting for "American" English and expect to bring on some new people real soon - thanks for the suggestion!

What a cool service! Who are the instructors? Can anyone sign up or do you interview them?

All of our instructors undergo a thorough interview process before we bring them on board :)

Is it a marketplace?

Not sure what you mean, but we interview each teacher and design the curriculum for each of our courses. We may move to an open marketplace in the future, allowing people to come on board through some sort of automated vetting process.