Within the few choices in pocessor in the Project Ara now there is another one. Google announced that it is working with Marvell and NVIDIA to bring to their application processors as options for the Project Ara. NVIDIA Tegra K1 and Marvell PXA1928 will be joining Rockchip as options for this project.
For the AP modules, we have been working with our friends at Marvell and NVIDIA to create two separate reference designs and form factor module prototypes around their PXA1928 and Tegra K1 processors, respectively, using a Toshiba UniPro bridge ASIC to connect to the on-device network. You can anticipate seeing these as part of the reference designs in our upcoming MDK v0.20 release. (The Rockchip AP with native UniPro that we blogged about previously is coming along nicely and will be ready in time for our Spiral 3 prototype in the Spring.)