Thanks Anshuman :) You have raised a rather curious question about how do you get a user on-boarded to a new app altogether. Firstly trying a health app will be different that other apps because it is strictly goal oriented and helps the user keep on track with something that might be able to prevent life threatening situations.
I also think the app can be made sticky in two ways. First, we could make the ecosystem of healthcare such that the app is not an additional burden but solves multiple pain points eg. managing patient records, doctor’s appointment, medicinal inventory, insurance claims and health related communication all in one place. Second, we could think of adding a fail-safe by building the app experience for the patient along with his/her caretaker. As I have noticed in personal experiences, someone close to you in your family often takes charge of ensuring the patient is regular in consuming his medicines. It would interesting to add this individual as a secondary consumer of the app and act as a regulator which will in turn ensure the patient is maintaining his/her desired goals.