People also die because of late or never materialized medical technology. We just prefer that people die from inaction (because is "normal") than from mistakes. This may be psychologically attractive because we avoid SEEING all the blood and dead bodies, but probably not the best way to minimize death and suffering.
Of course this is nothing new (Economic version: "That Which is Seen, and That Which is Not Seen"). Just another cognitive bias.
There is some more-or-less optimal middle ground between too little and too much regulation, but I don't think we're on it now. In fact, maybe it would be worthwhile to have a two-tier system, one for ordinary medical devices, another for experimental "this will probably kill you but perhaps you have nothing to lose" situations.
Off-topic, but I'm curious how you handled that situation. Personally, a safe-guard I might build in would be to audit our code by an independent third-party. Was this at all feasible in your situation, and/or how did you handle QA?
Well... External QA for app which costs 2.99$ (or less at times)? No. We just tried to make sure it worked properly - some code reviews, several unit tests to cover some nasty edge cases and that's it. I really hope everybody is alive and well. :)
Also it did help that the users grew confident in it over time. It was not like these overnight success stories (not even success story) which you hear all over the news :)
When I was a kid, volunteering at a hospital for Community Service, I was assigned a task to transfer pills from bottles to those plastic + foil single serving wrappers using a hot glue machine, and deliver said pills to the wards. I had no training, supervision, or QA/QC in this job.
Or, you know, people die.