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Full user review
"All I want and more in a very readable interface."
Much more than just a regular and scientific calculator: things like financial and trigonometric calculator faces. Many included customization skins. All kinds of conversions between various systems of units are built in.
The only conversion that I use often and that is missing is currency conversion, which is available on Apple's included OS X Calculator. But, the interface is much sleeker. Come to think of it, there is no religious conversion function, either <g>.
More reminiscent of the pocketable Texas Instrument and HP calculators of days gone by (does anybody carry these anymore?), and for $10, it's a steal.