Looks like a well designed product, make sure you use https for login and registration, and here is a list of other web app vulnerabilities that you can avoid: <a href="https://www.owasp.org/index.php/Top_10_2013-T10" rel="nofollow">https://www.owasp.org/index.php/Top_10_2013-T10</a>
Very cool. Will be useful.<p>One side note is that the registration and login pages don't use https. Sending from the app to your service should be secure as well but not as important as the register and login pages.