Android RPN app?

[Ren]

Greetings,
I am curious which RPN calculator app you use on your Android device.
What do you like about it?
What don't you like about it?
I'm leaning toward one that will have the look and feel of a 15C or 16C, or maybe 48G.
I'm willing to pay (~$10) for a decent app that doesn't track or spy on me.
A search of "Android RPN" on this site only returned a thread that I didn't see any apps.
Thank you.

P.S. I am not sure if I should be using the "poll" option for these questions.