Google is building a version of its Google Play store for Project Ara. The marketplace will allow developers to sell their custom modular components directly to consumers much like apps are sold today.

During a recent speaking engagement at a Purdue University event, Project Ara director Paul Eremenko said there was still a lot more they need to do in terms of ironing out the technical risks associated with the project. That said, there are probably at least two additional prototypes left to build.

During the market pilot, Eremenko added, they'll have a lot to learn about how people interact with the device.

Whether or not Project Ara is truly a viable solution in today's smartphone market remains to be seen but naturally, Eremenko is exuding with confidence. Key to its success, he noted, is whether or not they can span price points that range from a feature phone to a very high-end device.

Last month, the project lead revealed that Ara will run a modified version of Android Lollipop. What's more, users will be able to swap modular components (except for the CPU and display) without having to power down their device.

Eremenko revealed at the time that Google would sell modules through an online store although his latest speech provided much more detail on the subject. We still don't know how much individual modules will cost or how many will be available through the online store initially however.