For what is it useful?
 

Hey,
for what is this software useful? Does I need something like this, if I use Numbers or Excel? Are there any advantages? Thank you!

Thanks for checking out OmniGraphSketcher!

The main difference between OmniGraphSketcher and something like Excel or Numbers is that OmniGraphSketcher lets you draw your graph and edit it via direct manipulation instead of being dependent on data entered in a spreadsheet. OmniGraphSketcher also will plot your data, but you can't do any mathematical calculations with it other than a simple best-fit line.

Ah ok - thank you! :)