I have an old HP 15C RPN scientific calculator.

- I know where the buttons are without looking.

- It has functions my Android calculator does not have (directly or that I know of).

- It has a strange satisfying tactile feedback.

- It never interrupts me. Ever.

- It never distracts me. Ever.

I reach for it frequently.

Haven't used one since the day I finished school. I still have it though. It's like an artifact from another time...

I think you accidentally a verb.

But, yes. Casio fx-991EX. It's designed for schools, I think, but at the time it was the most advanced one they made that wasn't a graphing calculator, since I figured that if I ever wanted to draw a graph I'd just fire up "Grapher", which is still bundled with every Mac.

In about a decade I think I've done that once. The Casio is great.

Looks like it's discontinued now? I guess the fx-9910CW is the replacement. They made the buttons circular. Weird.

Does Windows Calc.exe count as well? :-))

Mines are stored, but I use the hp48 emulator regularly.

There's a farm here in Zurich where we buy a lot of our groceries. The store is unmanned. You use their calculator (or your cellphone calculator) to add up what you're buying then use your phone to scan a QR code and pay.

My kids often use their hands, I sometimes use paper and pencil

I still use a high school calculator for doing pen and paper maths. Stuff like figuring out when functions change sign. I find it less distracting than a code editor

I actually own one, a Casio. Simple reason, I'm a ham radio operator and you need one for the exams.

I use a Casio. Not just calculator, but for any tool, I try to avoid using my phone. A phone is a rabbit hole. Once you pick it up, you never know what notification will interrupt your flow. Besides, for these utility apps are difficult to monetize, it's hard to find one that isn't bombarded with ads. Even if luckily you find a perfect one, the creator might lose interest and stop maintaining it next year, forcing you to change your usage habits.

Nope, spotlight search handles basic calculations, python repl the rest of them.

I'm using a HP48G. [0]

It's just a joy to use and i also like it a lot design wise.

I like that it has a big display for 4 RPN rows, but i admit that that's something software calculators would even be better at.

It definitely has a nostalgic/romantic side to it for me.

Oh and for every day stuff, i really like to use Spotlight on macOS. It's really convenient: Command+Space, then just type the expression into the search box.

[0] https://en.wikipedia.org/wiki/HP_48_series

Oh dude, no. The instant I could start using something like https://www.wolframalpha.com/ in college over a decade ago, I did. I've never, not once in my life, had any desire to use a physical calculator when I could use a full blown computer instead. I think it's inferior even for pedagogy purposes - I can't screenshot and make Anki cards out of a TI-84.

"Do you still physical calculators?"

Well, no. My calculators don't bounce around so I have no reason to "still" them. /s

I have a calculator app that I use 99.9% of the time. I have a physical calculator around here somewhere. I used to use it when I'd have to tabulate physical items or when I'd been doing calculations for a long time. Short bursts on my phone are fine, but over hours is kinda troublesome.

Yes, not for its technological features but for its single-purpose-ness. If I'm working on paper, it's nice to pull out rather than a full on computer which also has all of my email on it.

I still regularly use a TI-35, and / or an old slide rule (I have three), and / or rough mental order of magnitude guesstimates.

Otherwise I use domain software for other tasks.

tl;dr: RPN - ride or die. ;)

Sometimes, for vintage reminiscing, a real HP48GX.* It got me through AP Calculus BC, SAT-I, and EE/CS. And doubled as a learning TV remote & TV-B-Gone. I also have a virtual HP48 on my phone, tablets, and computers.

In middle school, I had an HP 32SII. I remember being able to hear** either the processor clock or data line(s) of each of the 32 and 48 because one or more components acted as inadvertent audio oscillators that would make noises during computation (and during idle on the 48 because it had to keep redrawing the clock).

I've used R, MATLAB, pspice, and Mathematica in the past.

I'm a fan of Xcas and Wolfram Alpha now.

* I also have a collection of HP 48[GS]X cards, the printer, and the overhead projector adapter. In lieu of the overpriced official HP 48G to computer RS-232 interface cable, one can be easily made from a Sony CD-ROM audio cable.

** With my much younger ear pressed up to it.

I don't, but I sometimes see them used here in Japan. Some small-shop operators use them to add up charges and show the total to the customer. I was recently in the office of a small company, and I noticed that the bookkeeper had a calculator next to a pile of paper (receipts?) on her desk. She also had a computer in front of her with a spreadsheet on the screen.

When I moved here forty-three years ago, it was common to see abacuses used in similar situations. There's still an abacus school [1] not far from where I live, but it's been a long time since I saw one in use.

[1] https://maps.app.goo.gl/nvTg4hfSjTcba47c8

Yeah I still use my good ol' TI-83+ occasionally, but I'm a math instructor, so obviously. Most often I'll just use GNU `bc` though.

We are getting away from them in the classroom though; just started piloting a program where students use the Desmos app on their phones (requested to be in airplane mode) in class, and we have a department set of air-gapped phones with Desmos pinned for students to use on exams.

I have Sharp EL506T and it serves me well. I don't use it very often, mind, but it still happens semi-regularly.

The biggest reason for me are physical buttons and the fact I know the layout and capabilities. I'm just faster on physical calculator than on Android app.

But to tell the truth, usually I just use Speedcrunch on my computer. Or spreadsheeds. Or Python REPL.

I use a SwissMicros DM16L (a HP16C clone) because I like RPN and prefer physical buttons over a touchscreen.

I keep my TI-84 at my desk and reach for it maybe once a week. Usually for money reasons though, not so much for work stuff.

Yes, I have a Casio fx-9750GIII and I love it. I still haven't found an Android app or website that can do everything that I need (basic functionality), but in general:

- I need physical buttons. I often find that on touchscreens I mistype something and I don't notice.

- The history feature. Maybe I want to do a serial task or calculation, and I can just replace/correct one of the formulas in the history and it automatically recalculates all of the expressions that came after it.

- I have written some micropython code / utilities for the calculator and I use it all the time.

- I don't want to context switch to do a quick calculation. On my PC I have to open up a new terminal or a website (I might be offline, so I have to hotspot and then connect the wifi and ...) and interrupt my existing work or I have to frequently switch between a PDF or latex or whatever that I'm working on.

- Typing out `sin` or `np.sin` or `sin^-1` on PC is both longer and more error prone. It gets very frustrating very quickly.

- The numerical solver is a godsend. Try solving for the roots of an expression like `xe^x = 10` on your PC without internet. Or with an android application. On my calculator it's just a few dedicated button presses. On the PC, I have to use isympy and typeout `nsolve(Eq(x * exp(x), 10), 1)`, and you wouldn't even get a proper graphical display of the expression while you are typing it.

I still have them, also a slide rule, but no, I don't use them. It is essential to have these for when the grid breaks like it currently has in Mississippi for over a week. I also have multi-decade-storage batteries for them.

- I have a HP 16C, mainly for doing number conversions (DEC-HEX-BIN) and binary arithmetic.

- I have a HP 15C to take with me all the time (due to its small form factor).

- I have a HP 48 GX as main calculator, it is most feature complete and has a clock and alarms. I use it a lot for time calculations.

- I have a HP 48 SX, but did not use it much any more after acquiring the 48 GX.

- I have a HP 10bII+, which was a gift of my brother in law when he saw my obsession with HP calculators. I do not use it much, as I am not in financial stuff.

- I have a HP 41 CV, which is less capable as my 48 GX, but I somehow love it so much, that it resides on my desktop and is used a lot.

- I have a Casio Classpad fx-CP400, which I use when I tutor my nephew - it is the best fit for high school requirements (in Germany).

- I have a bunch of TI nspire and voyagers and a TI 83 plus, that I never use.

- I have a TI-92 plus which I used a lot in the past, but I do not like it anymore.

- I have a Casio FX-730P, which I like to write little programs for.

Not to mentions my collection of slide rules.

TI-30Xa still sits on the corner of my desk along with a pen and small notepad. I use it 2-3 times a week. Still faster to reach for it than find the calculator app on my phone or PC for simple tasks.

During my bachelors, I was using a Casio FX-991ES+. It was a beautiful calculator compared to the hand-me-down Fx-82 VPAM. And pretty popular with the folks of my age that time.

During and after grad school, I was using Mathematica or NumPy/Sympy quite a bit. But it felt like using an overpowered system to do basic assignments. Think of taking a Bugatti Veyron for grocery shopping. I indulged myself with another physical calculator - this time a Casio FX-CG50 with a color display and python support. I use it whenever I do self-paced courses or reading the occasional stats/ML paper.

HP-16C Casio fx81