Crash reporting, probably.
Tap for spoiler
They gonna rat you out to the feds if you divide by zero.
My recommendation: get rid of that app and go for a zero-tracker one:
... or any other great FOSS calculator out there.
I work for a company that requires everything to have a privacy policy that meets some minimums. We're technically not supposed to even use Google websearch because putting any question into it potentially sends company information into the world and out of our control. That one's not really enforced, thank goodness.
Without a privacy policy, I guess the calculator app could scrape the numbers you're entering, plus, idk an email and a OneNote entry for context, to reverse engineer the latest doodad we've been designing.
It's difficult to imagine what numbers from the calculator alone could be used for, but combine it with other information and you've got a problem.
If there are only two digits after a decimal and less than four digits before, you could probably figure out if someone was doing budgeting using their computer. Like if the user imput is:
99.99 + 27.63 + 127.48 + 4.99 + 2.99 + 10 + 283.57
.....that looks a lot like someone calculating monthly bills and expenses.
Because Google Calculator collects everything, just like any other Google app (except for Pixel Launcher probably).
stockpile on handhelds because soon even those are going to be data connected