Fractal Fr0st is a handy fractal software, help you view and modify fractal flames in realtime, as they are being rendered on screen.
It comes with an elegant and easy to use GUI and powerful python scripting. It is built on top of flam3, but also supports alternate renderers such as flam4 (for GPU rendering).

The license of this software is Free, you can free download and free use this graphing software.