You don't need the data. Hire UX experts, set up focus groups, dogfood your team, read bug reports from your users. Anything else is an invasion of their privac

You don't need the data. Hire UX experts, set up focus groups, dogfood your team, read bug reports from your users. Anything else is an invasion of their privacy and a sign of disrespect for the customer. There are exceptions, though. If you can improve safety of your product by in-depth analysis (cf. FADEC [0]), and the customer is on board (no pun intended), go for it. [0] https://en.wikipedia.org/wiki/FADEC https://en.wikipedia.org/wiki/FADEC