One thing I noticed is that the username is case-sensitive, which it wouldn't be in the web interface (my phone wanted to log me in as Pizaaplanet, which would always throw an "incorrect password" error, but pizaaplanet and the same password worked just fine).
Also, bear in mind that some keyboard applications will add a space after any word you write, so make sure you're logging in as "Supertails" and not "supertails" or "Supertails ".
There might be more to it. Like I said, this app is pretty buggy - we think we fixed most problems, but it's very possible that we missed something. Try fiddling around with capitalisation and such and let me know if that does anything for you.