The Study Kit software appears to have been in testing for several months now. The company quietly put out versions of Study Kit's iOS and Android apps at the end of March, at the same time as it offered a Study Kit Chrome extension, but it wasn't clear at first what the software was for as the apps could not be accessed without an approved email address. Speaking to TechCrunch, a Google spokesperson said that the company was "in the early stages of designing the Baseline Study" and was "exploring ways to make it easy for participants to share their health information and habits with researchers on a routine basis." The apps, the spokesperson confirmed, were "one route" Google was testing with pilot participants of the Baseline Study program. If the apps are used in the wider Baseline Study program, then they will only be available to people who have enrolled in the program.

There are similarities between Study Kit and Apple's ResearchKit, but Google's project is potentially more ambitious and far-reaching than the Cupertino company's effort. Where Apple's open-source project is focused on letting medical organizations set up research projects on specific topics that Apple users can contribute to, Google's study is out to define a perfectly healthy human — a mission that could have lasting implications on medical science.

If any organization has the reach to do such a thing, it's Google. With more than 1 billion Android users, Google is particularly well-placed to harvest health data from project participants from around the globe, and with monitoring apps on iOS and Chrome too, the company should be able to cut down on selection bias and get a scientifically significant sample. That is, if people don't mind signing up to be studied as part of the company's mission to find what characterizes a healthy person.