The native calculator starting with elementary OS 0.3 Freya. It integrates perfectly into the elementary eco system.

Authors: Marvin Beckers

Links: Launchpad

Installation

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elementary

Add a repository for elementary version 0.3 to install the software, by entering the following commands in a terminal:

sudo apt-add-repository stock && sudo apt-get update
sudo apt-get install calculus

Originally developed by Marvin Beckers as a third-party app for elementary, called “Calculus”, it is now the offical calculator of elementary.