Google's Project Ara

Project Ara is the codename for an initiative by Google that aims to develop an open hardware platform for creating highly modular smartphones. The platform will include a structural frame (endoskeleton that holds smartphone modules of the owner's choice), such as a display, camera or an extra battery. It would allow users to swap out malfunctioning modules or upgrade individual modules as innovations emerge, providing longer lifetime cycles for the handset, and potentially reducing electronic waste. A market pilot for Project Ara is scheduled for early 2015 with a target bill of materials cost of $50 for a basic grey phone.  The project was originally headed by the Advanced Technologies and Projects team within Motorola Mobility while it was a subsidiary of Google. Although Google had sold Motorola to Lenovo, it is retaining the project team who will work under the direction of the Android division.

Project Ara

Project Ara smartphones are composed of modules assembled into metal frames
Developer	Google, Motorola, Linaro
Manufacturer	User
Product family	yes
Type	Modular smartphone
Release date	6th feb, 2015
Retail availability	up to 7 years
Introductory price	minimal cost ~US$50
Operating system	Android
Power	modular battery
System-on-chipused	Toshiba-supplied for the first year
Website	Project Ara Project Ara Forum

Structure and features

Ara frames

Frame	Size	Rear module slots
Mini	45 × 118 × 9.7 mm	2 × 5
Medium	68 × 141 × 9.7 mm	3 × 6
Large	91 × 164 × 9.7 mm	4 × 7

Ara Smartphones are built using modules inserted into metal endoskeletal frames known as "endos". The frame will be the only component in an Ara Smartphone made by Google. It acts as the switch to the on-device network linking all the modules together. Two frame sizes will available at first: "mini", a frame about the size of a Nokia 3310 and "medium", about the size of a LG Nexus 5. In the future, a "large" frame about the size of a Samsung Galaxy Note 3 will be available. Frames have slots on the front for the display and other modules. On the back are additional slots for modules. Each frame is expected to cost around US$15. The data from the modules can be transferred at up to 10gigabits/sec per connection. The 2×2 modules have two connections and will allow up to 20gigabits/sec. This is to defer its obsolescence as long as possible.

Modules can provide common smartphone features, such as cameras and speakers, but can also provide more specialized features, such as medical devices, receipt printers, laser pointers, pico projectors, night vision sensors, or game controller buttons. Each slot on the frame will accept any module of the correct size. The front slots are of various heights and take up the whole width of the frame. The rear slots come in standard sizes of 1×1, 1×2 and 2×2. Modules can be hot-swapped without turning the phone off. The frame also includes a small backup battery so the main battery can be hot-swapped.  Modules are secured withelectropermanent magnets. The enclosures of the modules were planned to be 3D-printed, but due to the lack of development in the technology Google opted instead for a customizable molded case. 

Modules will be available both at an official Google store and at third-party stores. Ara Smartphones will only accept official modules by default, but users can change a software setting to enable unofficial modules. This is similar to how Android handles app installations.