How RunKeeper Could Become the Facebook of Fitness | Playbook: Now RunKeeper, the company behind one of the original health and fitness apps for the iPhone, has revealed an ambitious new plan that it hopes will make it the Facebook of fitness, a one-stop location for all of your important health information. Imagine having data on your blood pressure, cholesterol, diet, cycling output, heart rate, REM sleep and BMI, all continuously updated from a slew of third-party gadgets and services.