Project Ara, the modular smartphone initiative announced by Google last year, is taking shape after the first Module Developers Kit (MDK) was released today.

Among the information is an 81-page document that details the of customization open to developers, and thus the kind of things that we end users can hope to expect from our devices, although the project is still at a very early stage.

Screenshot 2014 04 10 15.48.02 730x355 Googles modular phone project begins to take flight as first resources for Ara are released

Interesting nuggets include three different sized ‘endos’ (phone chasis); the potential for multiple batteries, which can be swapped out without turning a handset off; plug-in peripheral devices like a Pulse Oximeter Module, which measures blood oxygen saturation, and more.

Screenshot 2014 04 10 10.31.09 730x564 Googles modular phone project begins to take flight as first resources for Ara are released
The first Project Ara Developers Conference takes place next week at the Computer History Museum in Mountain View.

You can access the MDK documents in the link below: