Even if you only got a whiff of the product demo sessions at the Health 2.0 Conference in San Francisco this week, you noticed: sensors are getting smaller, cheaper, and more closely integrated into tools we already use.

Consider Pulse Sensor, a dime-sized device that uses a beam of light to measure a person’s heartbeat. For $25, customers get a sensor kit that plugs directly into an Arduino microcontroller, the staple device of any DIY hardware hacker. Attach the sensor to an earlobe or fingertip and the light beam measures changes in tissue volume to gauge a person’s pulse. To date, the company has already raised over $18,000 on Kickstarter.

The other demo that caught my eye was the Google+ health challenge app from a group at CTIS, the winners of the Body Media challenge. Through their armband devices, Body Media uses a number of sensors to figure out how much someone moves and sweats during activity, giving an accurate read on how much energy is burned during the day. (I reviewed this product for Wired magazine back in June 2010). To win the challenge, CTIS built an extension to the Google+ platform that allowed users to create custom health challenges between a group of friends or colleagues, such as competitions to see who loses the most weight over 30 days, or who bikes the most miles in a week.

The idea of creating online health challenges isn’t new. But really, who needs to visit *another* website to track their health challenges? As we’re seeing with news, shopping, and entertainment, people want their online experience streamlined. The fact CTIS built their app into another social platform is key. Zynga has more or less cornered the Facebook game market; I’m waiting to see who will step to the plate with health apps.

Photo via Flickr / Magnet 4 Marketing dot Net

Brian Mossop is currently the Community Editor at Wired, where he works across the brand, both magazine and website, to build and maintain strong social communities. Brian received a BS in Electrical Engineering from Lafayette College, and a PhD in Biomedical Engineering from Duke University in 2006. His postdoctoral work was in neuroscience at UCSF and Genentech.

Brian has written about science for Wired, Scientific American, Slate, Scientific American MIND, and elsewhere. He primarily cover topics on neuroscience, development, behavior change, and health.

Contact Brian at brian.mossop@gmail.com, on Twitter (@bmossop), or visit his personal website.