An audacious effort by Google Inc. to upend the way smartphones are designed, built and sold has hit a snag on the way to Puerto Rico.

Google’s Project Ara is designing a “modular” smartphone with components that can be replaced and upgraded through a hardware marketplace similar to an app store. Googleplanned to begin selling the device in a pilot test in Puerto Rico this year, in partnership with big Latin American cellular carriers OpenMobile and Claro, part of América Móvil.