Speaking of geeky calculator apps.
Like everything, a matter of opinion
Droid48 (exact emulator of the venerable HP48G) stands at the top of the pack imo.
Completely free.
No ads.
No intrusie permissions.
Develop structured programs.
standard flow control constructs
Variables stored with user-specified (friendly) name and survive reboot.
Move your developmenmt to companion app on pc (which is also free!) if you want to see your complicated program code auto-indented/color-coded on your big pc screen to better understand how it will be parsed.
Ridiculous number of math features.
Unit-aware calculations
apps and data stored in user-named hierarchical directories, with top-down visibility of identifieirs.
variable values survive app close/restart and phone reboot intact (with proper settings)
Well-documented, static programming language since mid 1990's. (don't worry about having to re-learn anything, this doesn't change)
Boatloads of free resources and forums
many high level tools... too many to mention. Read about more starting my 3rd post here;
http://www.eng-tips.com/viewthread.cfm?qid=313111
What's bad about it:
- Plotting is lousy compared to other smartphone apps.
- Ease of learning is not a strength. But worth the invesment if you would like to have your own customized calculation at your fingertips......(ok, could also do that in google sheets / ms excel, but not all problems are easily formulated in that manner without script/vba... which is not present in android versions)
Why is it so good? HP spent a boatload of time figuring out how to create and perfect this kind of powerful interface onto a calculator roughly the size of a phone (back when apps were not a thing... only a few UI's to choose per manufacturer). There was a team of high-powered folks that rode the project for years. Having the most powerful UI was a strategic advantage for calculator sales and these guys were the best in the industry at it. Yes, you are dressing up your 2016 screamer to act like a 1995 clunker with a tiny fraction of computing resources (ram, processor, screen etc), but it doesn't bog down for me, and the UI is great.
