The first modular smartphone from Google is expected to arrive in 2015. While limited information is known about the final sale device it's just been revealed that changing parts will not only be easy but can be done at any time, even when the phone is powered on.
Project Ara team leader Paul Eremenko announced at LCU 14 that the smartphone of the future will be really easy to modify. The whole point of Project Ara is to do to hardware what apps have done to software – made them more accessible. This should mean more affordable hardware that can be added piecemeal to the Ara device.
Say you want to change the storage unit on your Ara when it's full, unlike most current microSD access the Ara will allow you to swap out memory while the device is on. Since other units are the same it could even mean swapping out your camera for a more suitable one for each photo – say a different lens type.
Even battery can be swapped out thanks to a reserve. Only screen and CPU will not be "hot-swappable".
Project Ara will feature a modified version of Google's Android L operating system and is expected to be out in January 2015.