Google has released the official Google+ app for the Apple iPhone. You can download it now directly from the Apple App Store.
Make sure that the version you grab is 18.104.22.1689 or later. Google mistakenly released a previous test version of the app which didn't have the stability and fixes that the latest version has. To check the version number, click on the gear icon on the top left of your app's homescreen and look right above the Help button.
Also, it's important to note that this app is just for the iPhone, not iOS in general. Google says that iOS5 is unsupported at this point and that iPad device support is coming soon. The search giant did not give details on timing for either though.
Google's official description of the app is as follows:
Google+ for mobile makes sharing the right things with the right people a lot simpler. Huddle lets you send super-fast messages to the people you care about most. And no matter where you are, the stream lets you stay in the loop about what your friends are sharing and where they’re checking in.
Google released Google+ last month in a clear attempt to compete in the social space with Facebook and Twitter. There are five basic components to Google+: Circles (for managing friends), Sparks (subscribe to specific interests for a constantly updated feed), Hangouts (video conversations with up to 10 friends at once), Instant Uploads (automatically uploads photos snapped with your mobile device), and Huddle (group chatting among Google+ peers).
Google+ has had an Android app from day one, but the iPhone version had to be approved by Apple first. Now that it has, Google+ is available on the two biggest mobile operating systems in the US. I wonder how long it will take for Google to release a Google+ for the rest of the mobile platforms.