Misunderstandings about noise in digital systems and environmental conditions in smartphones vs cars aside (well, no: your phone isn't operating at 100C or vibr

Misunderstandings about noise in digital systems and environmental conditions in smartphones vs cars aside (well, no: your phone isn't operating at 100C or vibrating in anything like the way a car does), your smartphone doesn't run reliably (relative to automotive reliability requirements) for a day. When a failure can kill someone, you have to take it much more seriously than when a failure slightly inconveniences a user while they restart the app.