The iPhone in your pocket can do a lot more than just play games or music. Used properly, that computer can help save your life. Consumer health apps are increasingly hitting iTunes. The latest one to appear today is Glooko (iTunes).

Glooko is a digital logbook for people with diabetes who have to check their blood sugar every day. There are dozens of glucose logbooks in iTunes, but almost all of them require manual entry. What makes Glooko different is that the company designed a $40 cable (sold separately) that works with six of the top glucose meters. You just plug it into both devices and it downloads your daily readings.

The app itself is free. It lets you mark whether the reading was done before or after a meal, add notes, and email or fax a 14-day summary to your doctor. The company charges for the cable. “What people want to do is download these readings into Apple devices,” explains co-founder Anita Mathew. “Many of these meters don’t work with Apple devices.”

There are an estimated 19 million diabetics in the U.S. alone, and 17 million of them test their blood sugar levels. By 2025, one in five people in the U.S. is projected to have diabetes.

Simply connecting these medical devices to iPhones creates a market opportunity, but this is just the first step. Once Glooko starts collecting diabetes data it could start to analyze it (although there are regulatory barriers—just plotting the data points on a graph requires FDA clearance). It could also charge for premium features. Glooko is an ambitious startup. It’s chairman and co-founder is Yogen Dalal (Xerox Parc, Mayfield Fund). Mathew worked for ten years in product marketing at Johnson & Johnson, where she helped launch several glucose meters. The third co-founder is Sundeep Madra.

Glooko also has some serious backers. The startup raised a $1 million seed round in November, 2010 from Chamath Palihapitiya‘s Social+Capital fund, Bill Campbell, Vint Cerf, Andy Hertzfeld, Judy Estrin, Bumptop founder Anand Agarawala, Kosmix co-founders Venky Harinarayan and Annad Rajaraman, Russel Hirsch, and Xtreme Labs. The company lends some of its Palo Alto office space to Social+Capital.

By ERICK SCHONFELD -TechCrunch on November 10,2011