Electrostatic Fields app for iPhone and iPad

Electrostatic Field is a beautiful, intuitive, multi-touch, gesture-controlled electric field simulator.

Manipulate and control an electric field with just your fingertips. Get an idea for how fields act by dragging and dropping point charges, holding and dragging to add charges, and double tapping to delete them.

Electrostatic Field is powerful.
If you want numbers for the field strength, double tap on an empty space for a probe that you can drag and drop.

Drag between charges to measure how far apart they are. Drag between distance probes to measure the angle between two. Tap anything to modify it.

The field is yours to control, learn about, and understand.