
The service provides small businesses with access to existing Google applications through a customer domain instead of an '@gmail.com' account.
The search firm unveiled its domain hosting service in February with the slogan Gmail for your domain. The service offered only email hosting and has several tens of thousands of active domains.
The expansion prompted Google to rename the service to 'Google Apps for your domain'.
Businesses and individual domain owners will be allowed to make some customisation to the services. They can, for instance, replace the Google logo with their company logo and share contact lists between accounts.
The overall look and feel is largely similar to that of the existing Google services.
The Google services are seen as an assault on Microsoft, which is developing numerous online services for small businesses as part of its Live software strategy.
Microsoft is offering free domain hosting, an online calendar, messenger and collaboration tools.
Microsoft also plans to introduce 22 online business applications including customer relationship management for companies with up to 10 employees paid for by online advertisements.