CalcPad+ is a clean and straightforward calculator app optimized for iPad. Its Decimal-based calculation engine eliminates the floating-point rounding errors common in other apps. Press = repeatedly to repeat the last operation, use context-aware percentage calculations, and keep track of what you're computing with the live formula history shown above the main display.
All calculations use Swift's Decimal type instead of floating-point Double. Operations like 0.1 + 0.2 return exact results, not approximations. Up to 15 digits of input and 10 decimal places of formatted output.
The right-hand value and operator from the first = press are saved. Each subsequent = press applies the same operation to the running result — handy for adding or multiplying by the same number multiple times in a row.
Pressing % without an operator divides the current value by 100. Pressing % after entering a second number following an operator converts that number to a percentage of the left-hand value before completing the calculation.
The current expression — left-hand value, operator, and right-hand value — is shown in gray above the large main display. You always know exactly what calculation is in progress.
Every stored value, intermediate result, and displayed number is a Decimal. Addition, subtraction, multiplication, division, sign toggle, and percentage conversion all operate on Decimal values end-to-end. Results are formatted with NumberFormatter at up to 10 decimal places so trailing zeros are trimmed automatically and thousands separators are inserted where appropriate.
When you press = for the first time, the right-hand operand is saved as the repeating value. Each additional = press uses the current result as the new left-hand side and the saved repeating value as the right-hand side. Entering a new number or tapping an operator clears the repeating value immediately, preventing accidental repeated calculations.
Digit buttons are orange. Operator buttons (+, −, ×, ÷) are blue. The utility buttons AC, ±, and % are light gray. The equals button is pink. The decimal point button is green. Color coding lets you find the right button at a glance without reading the label each time.
When the divisor is zero, the app throws a CalculationError.divisionByZero and displays "Error" on the main display. All internal state — stored value, operator, and repeating value — is reset automatically so the next calculation can begin immediately without needing to tap AC.
Tap the orange digit buttons to enter the first number. Use the green decimal point button for fractional values and the ± button to toggle between positive and negative. The value appears large on the main display.
Tap a blue operator button (+, −, ×, or ÷). The first number and the operator appear in the history line above the main display. Enter the second number the same way.
Tap the pink = button to compute the result. Press = again to repeat the same operation. Tap AC at any time to reset and start a new calculation.
"I tried several calculator apps and kept running into rounding issues with decimals. CalcPad+ is the first one that gets 0.1 + 0.2 right every time. The formula history above the display is a small touch but genuinely useful — I always know what I'm calculating. Great for iPad."
"Clean and simple with all the features I actually need. The repeat calculation with = works just the way I expect — great for quickly adding the same amount multiple times. Color-coded buttons make it feel intuitive from the first use. No unnecessary clutter."
"The large buttons are perfect on iPad — I make far fewer input mistakes than with smaller calculator apps. The percentage key handles both simple and compound percentage cases correctly, which a surprising number of apps get wrong. Reliable and pleasant to use every day."
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