Best calculator – Solve - Graphing Calculator Review

I'd like to see a swipe up or down that stores history for each calculator, erasable of course. Also maybe a undo/redo. Oh and maybe more color choices for the calc's like unlimited with a palette selector or the RGB number. Awesome guys! One issue where is the percent symbol? I use for tips all the time like 23.67 x 15 % to get the proper amount very handy.
Review by Chad-RS on Solve - Graphing Calculator.