Obsidian Calculator - Classic

Your default calculator is holding you back. It's time to switch.

Obsidian Calculator is the dark, premium calculator you never knew you were missing. Jet-black. Buttery smooth. Built for people who actually care what their apps look and feel like.

IT LOOKS UNREAL

Pure obsidian-black display with bold 3D circular buttons that feel almost physical when you tap them. Every press triggers a crisp ripple animation that makes the whole experience oddly satisfying. This is not your phone's built-in calculator. This is an upgrade.

IT REMEMBERS EVERYTHING SO YOU DON'T HAVE TO

Obsidian silently logs your last 100 calculations in the background — automatically, no setup required. Close the app, reopen it tomorrow, your history is still right there. Tap any past result to pull it right back into the display. Done with it? Long-press to clear the whole thing in one shot.

IT'S SMARTER THAN IT LOOKS

Smart AC slash Backspace — the button switches contexts automatically, so one wrong tap won't nuke your entire calculation mid-entry

Repeat Equals — tap equals again to keep repeating the same operation over and over, no re-entry needed

Seamless chaining — jump straight from one operation to the next without hitting equals at every step

Precision math engine — handles big numbers correctly where other apps start producing weird rounding errors

Auto-scaling display — your digits shrink just enough to stay perfectly readable, no matter how long the number runs

Portrait-only layout — single-handed, no distractions, no wasted space, just clean math

OPTIMIZED FOR EVERY ANDROID DEVICE

Runs flawlessly on Android 7 through Android 16. The deep black theme is a dream on OLED screens — looks gorgeous and saves battery at the same time.

You'll open it to do math. You'll keep opening it because it just feels that good.

Download Obsidian Calculator. Your calculator app era starts now.