http://toshl.com/ http://toshl.com/ This is a similar product that already has native apps for many mobile platforms and it's free to use (there is a pro accou

http://toshl.com/ http://toshl.com/ This is a similar product that already has native apps for many mobile platforms and it's free to use (there is a pro account with some additional features). disclaimer: I'm friends with the folks who built this, I just wanted to post this here for comparison.