US Internet colossus Alphabet on Tuesday revamped Google+ online social network focused on people's interests, and tuned for smartphones or tablets. "We're starting to introduce a fully redesigned Google+ that puts Communities and Collections front and center," director of streams Eddie Kessler said in a blog post. "Now focused around interests, the new Google+ is much simpler." Google's social network was rebuilt for fast, consistent performance whether accessed through computer web browsers or mobile devices powered by Apple or Android software, according to Kessler. Google+ users interested in the new version will need to opt in at the social network. Google's social network launched Communities in late 2012 as venues to people to connect online based on things or ideas they are passionate about. The option proved popular, and an average of 1.2 million people join Communities daily, Kessler said. Google+ Collections launched in May of this year as a way to group posts by topics, and its use is growing fast, according to Google parent firm Alphabet. "These are the places on Google+ where people around the world are spending their time discovering and sharing things they love," Kessler said. Google+ launched in mid-2011 in a challenge to Facebook, which continues to dominated the online social network world. Ambitions for Google+ were scaled back earlier this year when the California-based Internet giant stepped back from using social network log-ins as credentials across a wide array of its offerings, including YouTube.