I like Calculator++: https://f-droid.org/packages/org.solovyev.android.calculator/
F-Droid
F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.
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I've been using OpenCalc, which works perfect for me
Simple calc in portrait mode, you put in landscape and you have a full featured scientific calculator.
Additionally it feature a unit converter and logical operations programmer mode
Nice, I like this one. Disappointed the units converter doesn't have pounds and ounces as a target, though. It only does pounds or ounces, not both. I tend to see a lot of quantities specified as pounds and ounces at the same time in my day-to-day activities.
Looks nice, it's going on my list of potential replacements
i'm kind of put off by the "don't even try to contribute without asking" part in the readme 😐
Best one I've found, been using it for a while.
A lot of these (opencalc, yetcalc) look similar, and so does Unitto, but so far this one seems the best so far.
It has more theme options, lots of conversions, and the haptic feedback feels natural enough to me :)
I just use the AOSP calculator. Havent needed more than that since i left school.
Micromathematics Plus.
Arity.
You can emulate a ti83+ with an app called Graph 89.
Dib2Clac is cool too
I've also been looking for some calculators and while I find some good interesting ones, all of them either look clunky or have a huge learning curve or are too simple. I want a simple scientific calculator, but they're all either too simple or too complex.
But, think about it. The calculator is designed to be a machine. Emulating that on a phone might artificially limit you. Maybe it's better if your calculator has a different user experience, maybe the UX for calculators needs to evolve. Try out the weird stuff.
I just open up Qalculate in Termux.
https://bitbucket.org/dhashoandroid/graph89-paid/src/master/
Edit: the ROM can be downloaded for free directly from the Texas Instruments website.
I'm still using mathdroid. Which I have installed but cant find on fdroid anymore?
I can't seem find another Foss calculator app that doesn't think buttons need to bigger than my finger and 0-9 should take up 3/4 of the screen.... I love being able to see history of my past entries and have a button layout similar to an actual scientific calculator.
A lot of these are great and this one came close, I found usability could be better.
Usually when I need a calculator it's when I'm doing something else, out in the rain etc. I'd prefer some more (higher contrast) theme options and at least vibration on keypress.
It's a beautiful calculator, but it's too much like typing on a glass slab.