The domain which is registered from the blogger is valid only for one year from the date of registration. You must have to renew the domain to retain your visitors. If you forget to renew your domain after a year, someone else can take the domain. If you miss the existing domain name it is very tough to achieve the same amount visitors with different domain name.
If you buy a domain using blogger or Google apps, it will be created in godaddy/ enom. There is one auto renew option provided by the Google apps itself which will remind you to renew the domain one month before. The cash will be debited from the credit card which is linked with the Google apps.
See the steps below.
Go to Google Apps link http://www.google.com/enterprise/apps/business/
Login to your domain using your credentials.
- Click on domain settings in the top menu
- Click on Domain names
- Check in the box for “automatically renew my domain registration every year”
- Click on Save changes button