Here I got 1 as the answer:

https://imgur.com/a/TH14QZn

Aha! So 1e100 doesn't work but 1^100 does. Ok thanks!

1^100 = 1 though

That's a typo in the response, I believe. The screenshot shows 10^100 (10 to the power of 100).

1e100 is a float.

HP42 on Android checks out

My favorite Android calculator is RealCalc. I've been using it since I got it for PalmOS about 25 years ago.

https://play.google.com/store/apps/details?id=uk.co.nickfine...

I use it too, but it also computes 0 instead of 1 for:

    e^100 + 1 - e^100