With winners announced and organizers now regrouping to analyze the next stages, the Novartis mHealth Challenge - held last weekend in San Francisco and giving away over $40,000 in prize money - has demonstrated that for developers looking to aggregate APIs together into a health-focused, consumer-facing end-product, there is still plenty of room to enter the growing market. ProgrammableWeb spoke to Cheryl Cheng, one of the organizers of the hackathon and winners from Sense.ly to see what other API developers can learn from the outcomes.