At a joint press conference this morning in Hong Kong, Samsung and Google announced the Galaxy Nexus, featuring a super-slim profile and 4.65-inch HD (720p) display.
The 4G handset, which was expected to be called the Nexus Prime, has a dual-core 1.2GHz processor and 1GB of RAM in a form factor similar to the Samsung Galaxy S, but thinner at 8.9mm.
The Galaxy Nexus can shoot 1080p HD video, and has a five-megapixel rear camera with LED flash and a front-facing 1.3 megapixel snapper.
The Galaxy Nexus is the first phone in the world to be powered by Ice Cream Sandwich, which has been designed as an operating system to work across both smartphones and tablets, enabling developers to more easily write new applications.
Ice Cream Sandwich will come integrated with Google+, the new social network that has gained around 40m members worldwide since its public launch in September.
Android 4.0 phone users will get access to an updated app launcher, holographic user interface, new homescreen widgets, and a multi-tasking app panel.
Google said that it has created a new font that is optimised for HD displays, while the desktop-class browser is said to be "significantly faster", with options to sync your bookmarks with Google Chrome.
Ice Cream Sandwich also features "the best mobile Gmail experience to date", in a new design that lets users swipe through their inbox and search messages even when offline. The calendar has been cleaned up too with a new look, enabling users to zoom into their schedules with a pinch.
Watch a video introducing the Android Ice Cream Sandwich below:
Andy Rubin, the senior vice president, of mobile at Google, said in a blog post: "People are at the heart of Ice Cream Sandwich. We rethought how you browse your contacts with the new People app, which combines high-resolution photos and updates from Google+ and other social services.
"It's also easier to capture and share your life with family and friends. Galaxy Nexus sports a high-end camera with zero shutter lag, automatic focus, top notch low-light performance and a simple way to capture panoramic pictures. Shoot amazing photos or 1080p video, and then edit and share them directly from your phone.
"This weekend marks the third birthday of the G1, the first-ever Android phone. Nine releases later, more than 550,000 Android devices are activated daily."
Simon Stanford, the head of mobile at Samsung UK and Ireland, added: "We're extremely excited about the Galaxy Nexus and the wide range of features it offers consumers.
"The collaboration with Google to launch the world's first smartphone featuring Android 4.0 Ice Cream Sandwich and a 4.65-inch HD Super AMOLED display is evidence of Samsung's continuing passion for innovation within the market."
Two senior figures at Android told Endgadget after the event in Hong Kong that Google is working on an Android 4.0 update for the Samsung Nexus S and other Android Gingerbread devices.
The Galaxy Nexus will be available in the US, Canada, Europe and Asia from next month. Pricing and availability have not been confirmed as yet.
Watch a video introducing the Samsung Galaxy Nexus below: