I use them time till time, some of them are really convinient and helpful in some cases. At the current time I like the most of all Happify (it's a really nice one for overcoming daily stress and making better your general emotional state), CycleCast (very nice fitness radio, in my case I prefer to make different exercises with a suitable music for them ), Fooducate (it's helpful for creating healthy eating habbits) and Sworkit (provides a nice base of videos with various physical exercises). I tried also some specific medical ones like Micromedex, MyChart and so on. They're nice ones too but in my opinion they can't replace professional medical help, the best ones were only those who helped me to keep fast communication with my doc and solve some organization issies in hospital https://idapgroup.com/blog/healthcare-mobile-app-development-future-hospital/ . I hope that they will be more upgraded in future.
Anyway such apps in general are rather effective for making healthier many people https://mhealthintelligence.com/news/the-advantages-of-mobile-health-apps-today-and-tomorrow and I think that it balances all their cons.
I use Lose-It. My A1c was 7.2 (it should be below 5.4) and in 3 months I got it down to 5.2 and lost 13 pounds. Get the basic app for free ... aftter a few weeks they offer you the Premium at a discount.
Since I use Quest via my gp for all my lab tests, I use MyQuest mobile app. I get results before I see my doc, so I can decide what I want discussed. Has the ability to see results in case of referral, and lets you look at results over time, and make appointments. Really easy....
Our doctor, clinic, and hospital use MyChart App. All of our test results are there, we get them quickly after the test. We can ask questions, request prescriptions, make appointments, and view our medical history. We like it.