Today Google has introduced a new universal login and sharing system called Google+ Sign-In. Similar to Facebook Connect, Google+ Sign-In is a single login for websites and mobile apps that lets people bring along some of their Google+ information. This means that they won’t have to create a separate username and password for third-parties.

The old version of the system will continue to be available. And while Google+ Sign-In will still offer options like two-step authentication, it will allow developers to add several new features. For example, starting today, when someone signs in to your website with Google, he or she will also be able to install your Android app on his or her mobile device with just one click.

With Google+ Sign-In and Circles, individuals can decide who to share with, if at all. As the company puts it, Google+ doesn’t let apps “spray frictionless updates all over the stream,” so app activity will only appear when it’s relevant. This is a great way to deter apps from spamming the stream while still giving members the option to share content with the right people.

Additionally, the company has introduced new buttons on Google+ for “interactive sharing.” Meaning that you can now direct people to relevant pages on your web and mobile apps to “buy” or “review” products, “listen” to a song, and so on. Google plans to offer more than 100 actions that you can add to your Google+ posts.

Google has partnered with Banjo, Beautyfish, Fancy, Fitbit, Flixster, The Guardian, OpenTable, Shazam, TuneIn Radio, and USA Today to (gradually) launch the new logins. All of the features mentioned above will be available on the web, iOS, and Android (with the exception of one-click installs, which only support Android). Developers building apps can learn more about including the Google+ Sign-In through Google’s Developer docs.

[Via: TechCrunch, Image credit: Kham Tran]