This is a free Apple (iOS) interactive all-in-one math App.

Great for individual student or classroom use:
Apple App Store Preview

THE SPINNER IS FINGER ROTATED WHILE THESE LESSONS ARE OBSERVED:

1) TIME CLOCK:
The tip of the spinner locates your “YOU ARE HERE” position while looking down on the earth from above the North Pole.

2) ANGLE MEASURE:
The Radian angle values scroll dynamically while the spinner is rotated. Equivalent Gradian and Degree values are indicated statically.

3) CIRCLE GEOMETRY:
Equations for circumference arc length, and circle sector area are stated with their respective values that also scroll dynamically as the spinner is finger-rotated.

4) TRIGONOMETRY:
Sine and cosine tracking dots follow their respective graphs as the spinner is rotated.
The design gives the ‘on-the-hour’ right-triangle side lengths for use in all six trigonometry equations (additional Graphs page shows their static shapes).

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