This is very similar to a Doodle, however lacks the clean / less-eye hurting visuals.
I would still recommend Doodle if anyone is still looking for an option in this field: http://doodle.com/
I would still recommend Doodle if anyone is still looking for an option in this field: http://doodle.com/
This project has been up since 2011 (check their blog), so I thought they must have known about Doodle already, and can solicit further feedback on why someone may prefer another project than theirs.
Regardless, I think it is always worth mentioning competitors and related projects, either for the creator to get ideas from or to see how they can work to differentiate themselves.