Oh, thanks for your very quick response. Its not like I really concerned about my referral, if I can't get that, its completely ok because at least I've introduced my friend to the world of bitcoin and your generous app.
If I may suggest, maybe you'd like to do what some other faucet do: each user have a certain digit ref. code which can be entered upon friend's signing up. That way, even if someone do what I did (directly go to google play instead of sending a direct link) he still can ask his friend to "please put 123456 on the referral column, its my ref number" and all clear