Amazon launched a new service called ‘Login with Amazon’ today that lets its 200 million active customers sign-in to apps, games and websites created by third-party developers using their existing account details.

It is, in other words, the same feature already offered by Facebook via Facebook Login and Google as part of its Google+ social network.

Amazon says it has seen “significant customer adoption” while trialing the service with Zappos and Woot – both Amazon subsidiaries. Zappos saw 40 percent of its new customers choose to register or sign-in using an Amazon account. Woot, meanwhile, says new customers picked Login with Amazon “two times more often than any other social login on their site” and that these users were also most likely to place an order through the service.

Developers can integrate Login with Amazon into their apps, games or websites for free. Amazon says the service can be added “in a matter of hours” and is based on the OAuth 2.0 authorization framework, which is already known as a widely adopted open protocol.

The idea is that users are far more likely to sign-up and experiment with an app or service if they’re able to do it with a single click. Filling out countless registration forms can create an awful lot of friction for new users, which negatively affects growth, engagement and monetization opportunities.

Facebook has seen a great deal of success with its own sign-in service, and Google is following with a near-identical feature set. Amazon, meanwhile, has been keen to push its own account profiles and ecosystem – this includes Amazon sign-ins for its on-demand movie rental and streaming service LOVEFiLM, as well as the expansion of its Amazon Appstore.

“Login with Amazon enables app developers and website owners to leverage Amazon’s trusted sign-in solution, allowing them to focus on providing a great experience for their customers,” said Michael Carr, Amazon Vice President, eCommerce Services. “Amazon customers now have a hassle-free way to quickly and securely sign-in to apps, games and websites, without having to remember yet another password.”

It remains to be seen whether users would prefer to sign-in with their favorite apps and services using their Amazon account, rather than their Facebook or Google+ profile. Nevertheless, it’s a clear indication that Amazon wants to increase its integration with other Web services and the functionality of its existing userbase.

mage Credit: EMMANUEL DUNAND/AFP/Getty Images