Redmond, Washington-based Mobisante, a smartphone-enabled medical device company, raised $4.2 million from WRF Capital, W Fund and members of the Alliance of Angels according to a statement from the company and an SEC filing. As part of the investment Mobisante added Managing Director at WRF Capital Loretta Little to its board.

The company also hired Marcus Y. Smith as its new chief financial officer and Dr. Bradley N. Younggren as its new chief medical officer.

Mobisante makes smartphone and tablet enabled ultrasound imaging systems. The tablet offering, MobiUS TC1, was the most recent addition to the Mobisante product line and it provides larger images, more powerful ultrasound probes, which enable providers to use the system for prostate and gynecology imaging. While the company's offerings all cost around $400 per month for the software, the tablet version has longer battery life -- 60 minutes of continuous scanning on the smartphone and 4.5 hours for the tablet.

Although the FDA cleared Mobisante for both its tablet and smartphone systems in 2011 the tablet software released in 2013. Since then the company has been increasingly vocal about how difficult it is for medical device makers to raise capital.

For a brief history of all smartphone enabled health devices, visit MobiHealthNews' timeline.