“We did crack the screen, and the phone doesn’t quite boot,” said Paul Eremenko, head of Google’s Project Ara, as he presented an engineering prototype of the first Project Ara phone during a webcast developer event in Mountain View, California, on Tuesday. Ara is an ambitious idea: a basic exoskeleton into which standard-sized modules can be connected to produce a completely personalized smartphone. Alongside the basics such as a processor, screen and battery, users will be able to add the networking, multimedia and other modules they require. “We want to make the smartphone hardware ecosystem more like that of the software ecosystem that underpins Android,” said Eremenko. The vision is nothing like other smartphones on the market, but it’s also far from a sure success, especially considering Google’s target market. The modular phones aren’t primarily aimed at the wealthy, gadget-hungry consumers that already have the latest smartphones, but at the majority of people on the planet who are still using feature phones: “the next 5 billion.” Through Ara, Google hopes to not only bring smartphones to more people but to increase the size and competitiveness of the hardware market, reduce the time it takes to develop a phone and make it easier for companies to enter the marketplace. Google plans to supply a bare-bones handset with a screen, battery, processor and WiFi module and leave the rest up to the market Users will then be able to buy additional modules to build the phone as they wish. The modules are made to a standard size measured in 20-millimeter units. In a prototype handset shown on stage, the exoskeleton has room for five 2×1 unit modules and two 2×2 unit modules. A WiFi module was built into a 2×1 module and the processing module was enclosed in a 2×2 module. Eremenko outlined the company’s basic plans for Ara and the software development work and future plans for the platform. Developers paid US$100 to attend the event, which was held at the Computer History Museum near Google’s headquarters. Left unsaid during Eremenko’s presentation is how a company would make money from such a device while servicing the “next 5 billion” people who were repeatedly mentioned as the project’s main target. Cost will be key and Eremenko said he recognized that would be a challenge. He’s targeting the bare-bones phone, the so-called grey phone, to have a $50 bill of materials. That’s not what the device would necessarily cost end users. “That’s something we will have to figure out downstream,” he said. Google hopes the grey phones will be widely available and easy to buy. “A grey phone could be shrink-wrapped and something you could buy at your local convenience store,” said Eremenko. “Your fire up your grey phone, run the Ara configurator and start purchasing modules in the marketplace.” Module prices will be left to companies that produce them with the expectation that competition will drive down prices. The standard size and interface used by the modules could also spark a second-hand market, but that could take months or years to get off the ground. Future developer events are planned, said Eremenko. At the next of those, Eremenko hopes his phone will work. “I wish I could make a phone call from stage, have my Steve Jobs moment, but we’ll have to save that for a future developer conference.” Martyn Williams covers mobile telecoms, Silicon Valley and general technology breaking news for The IDG News Service. Follow Martyn on Twitter at @martyn_williams. Martyn’s e-mail address is martyn_williams@idg.com