Studentsa are spending almost $200 each on their "graphing calculators".  I need to know if "graphing calculators" can be replaced with an IPod Touch.  Please leave a comment for us as we explore the possibilities.  Here are the current apps related to "graphing calculator" in the App Store. 

1. Have you ever used any of these?  Feedback?
2. What capabilities and or functions do "graphing calculators" have that you can't live without?  
3. Are there educational issues related to students having multiple more functions with Touch at their disposal that would cause a problem? 

Have at this.  What do you think?  I will be contacting these vendors and any others to ask some math teachers to test pilot these apps sometime.  What are the positives and negatives?  Issues with testing? Etc.