App Annie

Consumer spending in health and fitness apps also tripled during this time, according to numbers from App Annie.

The third-party analysis compared 10 telehealth providers' Google Play and App Store downloads over a four-and-a-half year period.

OptimizeMe, the Zurich, Switzerland-based life logging app that interprets wellness data users collect through apps and devices, will soon launch its second version under a new name, following an "amicable legal dispute resolution" with UnitedHealth Group.

When it comes to companion apps for connected devices, Fitbit's is the most downloaded in the health and fitness category and the second most downloaded overall.