Calculator Extended is a calculator app with the following features:
Scientific functions - available without having to turn your phone sideways, so they can be used with one hand
Visible history - view previous expressions to check your work, and press the up and down arrow buttons to re-run a previously run expression
Unit conversion - convert between common units, both metric and imperial
Better buttons - smaller buttons with margins to reduce errors, on a modal keypad to improve muscle memory
Clean design - no gradients, logos, or ads