(If you have any favorites that you think ought to be added to this list, please let me know.)

**Helpful Cellphone Apps**

**Camscanner**is a useful app that uses a cellphone camera to take a picture of a document, and then crops and sharpens the image and turns it into a PDF file. This is very useful for students who need to submit homework electronically. It is helpful to the instructor, because when the instructor receives a PDF of the homework, it is easy to add comments (link to Camscanner web page)

**General Websites**

**Wolfram Alpha**is a truly amazing site (link)

**Function Evaluators: **

**Function Evaluator and Grapher**(by Stefan Waner) (link) (very simple and flexible interface: You enter a function or multiple functions into a web form. Then you can either enter an x-value or multiple x-values into a web form to produce a table of values, or you can plot a graph.)

**Graphing Utilities : **

**GraphSketch**(by Andy Schmitz) (link) (very simple and flexible interface, easy to graph multiple equations or parametric equations, zooming done by typing into a form)**Meta-Calculator**(link) (very versatile, clear interface on multiple pages)**Desmos Calculator**(link) (versatile, but not immediately obvious how to use, user can save graphs by setting up a free account or linking to a Google account)

**Calculus**

**Secant and Tangent Line Grapher**(on Desmos Calculator)(EXCELLENT) (link)**Secant and Tangent Line Grapher**(by David Little of Penn State)(Getting browser to run this webg page is a pain!) (link)**Derivative Grapher**(by David Little of Penn State) (link)**Riemann Sums Calculators**

**Regression Calculators**

**Xuru's Regression Calculators**let you paste data in from a spreadsheet. The result is a list of coefficients. (link)**Arachnoid's Regression Calculators**lets you paste data in from a spreadsheet. The result is a list of coefficients and a graph. (link)**Had To Know's Regression Calculators**lets you type (x,y) data directly into a web form. The result is a list of coefficients. (link)

**Online Calculators for solving systems of equations**

**System of Equations Solver**(from the*Solve My Math*web site) Simple interface, but the asterisk * is necessary for multiplication. (link)**Algebra Solver**(from the*Quick Math*web site) Also a simple interface. The asterisk * is not necessary for multiplication. (link)

**Geometry**

(page maintained by Mark Barsamian, last updated April, 2020)