To make your account even more secure we recommend you enable enhanced security (two-factor authentication). You can use any app which supports Google codes for 2FA, below you will find a short list of apps we recommend:
Authy - An advanced app for 2FA. You can download it for your mobile device from the App Store or Google Play or install a browser extension to your Chrome browser (available for Windows, Mac, Linux). See how to set Authy up here.