Is it secure to login via Google...?
Absolutely! When you login to ZetaBee via Facebook, Google, or any of the other websites, you can be certain that none of your personal information (e.g. passwords, security questions etc.) will be available to ZetaBee or anyone else.
All ZetaBee knows about you is that you have successfully logged in via one of the sites.
Why should I login via these sites?
If you login via Facebook, Google etc., then you do not have to sign up for ZetaBee with yet another username and password that you might forget.
Creating accounts and registering for new sites is major a hassle for everyone and that's why ZetaBee doesn't need one. Simply login via one of the sites and you can immediately start using this website.