Google's second Project Ara developer conference has born all sorts of revelations, not least that the modular smartphone will launch first with a test program in Puerto Rico.

Now Google has revealed something else: the app that will help buyers design their Project Ara smartphones.

Project Ara is a "modular" smartphone whose components, including batteries, cameras, storage, processors, and more, can be swapped in and out at will.

The app, called Ara Configurator, will let users choose their modules, see how they'll fit together on the phone's endoskeleton, and design their external shells, then view their specs and price with a swipe, reports Engadget.

Automated customization

Google's Shell Maker API will make all sorts of things possible on the phone's outer shell, including applying photos to the Ara modules and more.

Google's Jason Chua even suggested the app could someday use your social network posts to help automate the configuration process - post lots of photos and you might need a better camera, for example.

Project Ara will launch in the second half of 2015 in Puerto Rico, and meanwhile Google is working on its third prototype for the project, dubbed the Spiral 3.

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