The market for wearable sensors has exploded to measure walking, running, and even your posture -- so why not sitting, too?

That's what the Rise, a $39 wearable sensor, is designed to do. The small device, which is about the size of a quarter, not only measures how often you sit, but it also pairs with your smartphone to motivate you to sit less.

The device comes at a rough time for sitting, which is so dangerous to our long-term health that researchers are calling it "the new smoking." By some accounts, men who sit more than 23 hours a week raise their risk of dying of heart disease by 64 percent -- even if they exercise regularly.

As Chris Fryer, co-founder of Rise parent company MVMNT Inc, told VentureBeat, the core problem is simple: Sitting is just too easy to do.

"Sitting is so acceptable. You walk into work and there's a chair just waiting for you. Even with a standing desk, it's really easy to default back to normal behavior," Fryer said.

That's where the Rise fits in. If Fryer and cofounder Morgan Redfield are right, before you can convince people to stand more, you first have to show them how much they sit. And that's the kind of thing you can only do with a wearable sensor.

The smartphone connection is big here, too. By syncing with smartphones, Rise can send users alerts when it detects they've been sitting too long, which is huge for helping them change their habits.

And then there's the gamification angle. Similar to what companies are doing with fitness trackers, Rise plugs into the iOS Game Center, letting wearers compare their activity with that of friends and family.

In other words, Rise's solution to your sitting problem is digital from end to end.

"What we’re solving is not sitting — were solving that sitting is easy and habitual," Fryer said.

Fryer and Redfield are looking to raise $80,000 to launch their device, which they aim to ship by next June.