☕ One-time purchase at the price of a coffee. No ads, no subscription, no in-app purchases.
Pay once – the app is yours forever. No surprises, no purchase prompts.
CustomKeys is a calculator you can tailor to your needs. Eight programmable keys keep your most-used values and functions always at hand – no more repetitive typing.
🔑 PROGRAMMABLE KEYS
Long-press any key to configure it as:
• Number – any value (e.g. VAT multiplier 1.19, material price, constant...)
• Function – operation (+, −, ×, ÷), square root √x, square x², percentage % or constant π
• MEM – memory key. Result saves automatically after =, tap to recall stored value.
📐 GEOMETRY FORMULAS
A row of geometry shape icons sits below the display. Tap a shape, enter dimensions, send the result directly to the calculator. Available:
• Circle – area, circumference
• Triangle – area, perimeter, hypotenuse (Pythagoras)
• Square – area, perimeter, diagonal
• Rectangle – area, perimeter, diagonal
• Rhombus, Parallelogram, Trapezoid – area, perimeter
• Cylinder – volume, surface area, lateral area
⚙️ CUSTOMIZATION
• Individual key colors – 9 color options per key
• Drag & drop to rearrange base keys
• Dark mode
• Display number size (large / medium / small)
• Left-handed mode – mirrored keyboard layout
• Sound and haptic feedback
• Slovak / English
CustomKeys is perfect for tradespeople, builders, merchants and anyone who uses a calculator daily. One purchase, no ads, no surprises.