You should really be using two-step authentication for your Google account, and if you are, then you should be using it with the Google Authenticator app. I used the text codes for the longest time, and I don’t know why, since the Authenticator app is easier to use, and more importantly, easier to hide and secure.
The Authenticator app is dead simple: it spits out a new 6-digit verification code for your account every 20 seconds or so for you to use when logging into other devices and computers, even when you don’t have a data connection on the phone. But since it gives up the last code someone would need to access your account, assuming they sussed out your password somehow, I don't let the Google Authenticator app sit in my app drawer without making it wear a disguise. If using Nova or another third-party launcher, you can change the icon and the name of the app as it appears in the launcher, and so Google Authenticator can become just another mind-rotting game to the snooping silbling/spouse/roommate.
And what's more is that you can use Google Authenticator for other apps and services that use the same sort of authentication, including Facebook, Buffer, and VPN services.