v1.0.0

The first public release of DumberKit: Calculator – a calculator and unit converter for keypad phones (Qin F21, Dumber Mini, Doov R77 Pro and similar), built on Fossify Calculator. No on-screen buttons: you type the calculation straight on the keypad.

Highlights

• Digits type numbers, * adds an operator and turns it into the next one (+ − × ÷), # is the decimal point, OK or the green Call key shows the result
• The usual order of operations and exact decimals (10 − 2 + 3 = 11, 0.1 + 0.2 = 0.3)
• Hold * for a palette of symbols laid out like the keypad: powers, square roots, parentheses, percent, ±
• History like a paper tape, ↑ / ↓ go through it; it's cleared when you close the app
• Calculator, unit converter and settings in tabs switched with ← / →
• Unit converter for length, area, volume, mass, temperature, time, speed, pressure and energy, in both directions
• System, light, dark, dark red and custom themes; blue icon by default, any other color can be picked
• Touch is off inside the app so nothing gets pressed by accident (can be turned on in Settings)
• Small (3.2 MB), no ads, no tracking, no internet access

Download dumberkit-calculator.apk below. Requires Android 8.0 or newer. See the README for the full guide to the keys.