You need an incredibly robust quality management system to even achieve certification (allowing you to place on the market) when creating systems which include life support function, or functions which potentially could kill a user. All potential changes both within and outside of the manufacturers’ control MUST be assessed and constantly monitored so such issues CANNOT arise.

No one should be able to legally place an unsafe app on the market, or legally perform changes to the app without the necessary checks and balances.

Medical device approvals in most countries are definitely not the wild west. Although they are not perfect.