Google has announced nine new Google+ features which bring the total number of key features to 100. Perhaps the most important of them all is number 100: anyone can sign up for Google+ - no invitation required.

The search giant's social network launched in late June on an invite-only basis in what was considered a field trial. Google says that they are far from finished with the Facebook rival but are confident that they have learned enough over the past 12 weeks to move the project from field trial to beta status and open the doors for anyone to join.

Hangouts were introduced when the service launched as a way to better connect with your friends. Basically it allows live video conversations with up to 10 friends at once. Google has now introduced Hangouts on your phone, compatible on Android 2.3+ devices with front-facing cameras (iOS support coming soon).

Other additions to Hangouts include Hangouts On Air, which will allow you to broadcast and record your session to a wider audience. Google is rolling this feature out to a limited number of broadcasters initially, with the first live test taking place tomorrow evening featuring will.i.am as the host.

Hangout users will now have the ability to share their screen with other viewers, an interactive sketchpad, shared Google Docs and named Hangouts, for when you want to join or create a public forum about a specific topic.

Google is also releasing a basic set of Hangout APIs for developers to build new apps and games. More information on the API can be found on the Google+ platform blog.

In addition to all of the Hangout updates, Google is bringing search to their social network. Type in what you are looking for in the search box and Google will return relevant people and posts on the topic.