One of the most secure way to connect to Google's Web Apps, e.g., Gmail, is to setup 2-factor authentication. Wherein not only do you need to enter your password to the Gmail login, you also need to enter a code that is sent to you via your phone or use a One Time Passcode (OTP) that expires after a set amount of time. This OTP code is often generated using a secure device that Google will send to you or by the Google Authenticator app that runs on your phone.
While this extra step in logging in your account significantly strengthen security, it is also quite annoying and tedious. Having to enter a password, then finding your phone, waiting for a new SMS from Gmail, and the inputing the code, results in many minutes of loss productivity every day. Multiply that by the number or Gmail users and you can see the frustration and loss in productive time is significant.
2fac4u is a set of applications (iOS, Watch, and Mac) that once installed on your devices allows you to login to any Mac running 2fac4u in the background for any Gmail account that you enable for 2-factor authentication. Once setup, the authentication is virtually 2 taps and less than 10 seconds.