Hi,This is my first post here. My app is MatCalc. MatCalc is easy to use yet powerful and flexible calculator. Its editable worksheet feature make it difference from other calculators out there. The free lite version is available (without worksheet feature). Please forgive my poor English ;-) iPhone & iPod touch versions Download MatCalc Pro Download MatCalc (standard version) Download MatCalc Lite (free version) iPad versions also available here Download MatCalc Pro XL Download MatCalc XL (standard version) Download MatCalc Lite XL (free version) MatCalc Website Screen shots and info of MatCalc XL for iPad on MacRumors Forums MatCalc is an expression based calculator for iPhone and iPod touch. User type the expression and press enter to get the answer. MatCalc has a built-in history which allow user to evaluate previously calculated expression and answer. The unique feature of MatCalc is MatScript, an easy to use worksheet which will re-calculate the entire history when user edit any cell in history. MatCalc is available in 3 versions with different level of capabilities Highlighted features -Expression based (formula calculator). User types in the expression and then press 'Enter' to get the answer. -Native iPhone keyboard supported with copy/paste. -Calculation history allow user to evaluate previously calculated expression and answer. -Worksheet like capability in MatScript mode.Automatically re-calculate the entire history when user edit any cell in history. -Save and reuse MatScript. Available in Pro version only. -Decimal, Hexadecimal, Binary and Octal mode -Thousand separator -SI prefixes shortcut. ie. You can enter 1M for 1000000 or 1m for 0.001. Electrical engineer will love it! -Build in math functions -Build in units conversion functions -Build in π,φ and Euler number -Unlimited user assignable variable -Email your calculation history. -And more!