Tamoggemon Software -> S60 -> TouchCalc Free
Like all other Tamoggemon products, TouchCalc is really easy to use. Take a look at the screenshots below to see what we mean:
TouchCalc handles just like a normal scientific calculator. In landscape mode, it is optimized for keyboard usage.
Five memory banks can be used to store calculation results for later usage.
Graphing functions on the go is a non-issue, too! However, graphing the functions above requires TouchCalc Free.