Support

Questions, bug reports and suggestions are all welcome at hello@sumicalculator.com.

Frequently asked questions

Why does Sumi show a fraction or a square root instead of a decimal?

Sumi keeps results exact whenever it can, like a Casio fx‑991. Press S⇔D to switch between the exact form and its decimal value, or turn off Fraction results in settings to always see decimals.

How do I see previous calculations?

Tap the history key (the clock icon) or drag up from the keypad. Tapping an entry brings its expression back for editing.

How do I switch between the light and dark themes?

Open settings with the sliders icon and choose Paper, Ink or System under Theme.

How do I change the angle unit or the number of decimal places?

Both live in the settings sheet under Angle unit and Number format, which offers Fix, Sci, Norm1 and Norm2 like the original.

How do I copy a result?

Long-press the result and it is copied to the clipboard.

How do I delete my data?

Everything Sumi stores lives on your device. Reset all in settings clears memory, settings and history; deleting the app removes it entirely. See the privacy policy.

What is the tip jar?

Sumi is free with no ads. If you enjoy it, the tip jar in settings lets you leave a small one-off tip through the App Store or Google Play. Tips unlock nothing and are never required.