Google's modular smartphone Project Ara is close to getting its first "fully functional prototype" and will see an official launch in "early 2015."

Project lead Paul Eremenko told Tech Report that most Ara modules will support hot swapping. Although the device will have to be switched off to change the CPU and display components, any others, including cameras and batteries, can be changed on the fly. 

The endoskeleton actually includes a small battery that provides "some seconds" of power to facilitate quick battery swaps. Google's Android L operating system has also been modified to support hot swapping. Modules will connect via UniPro, a royalty-free interface standard and the SoC vendor Rockchip is working on quad-core chip with UniPro onboard. The Rockchip chip will be based on ARM's Cortex-A7 core.

Eremenko anticipates Ara-compatible smartphones will cost $50-100, but the design allows folks with deeper pockets to spruce up their device with more exotic modules.