In October 2013, Motorola Mobility announced Project Ara, a concept for a modular smartphone platform that would allow users to customize and upgrade their phones with add-on modules that attached magnetically to a frame. Ara was retained by Google following its sale of Motorola Mobility to Lenovo, but was shelved in 2016. That year, LG and Motorola both unveiled smartphones featuring a limited form of modularity for accessories; the LG G5 allowed accessories to be installed via the removal of its battery compartment, while the Moto Z utilizes accessories attached magnetically to the rear of the device.