The app Triangles calculates all lengths and angles of the specified triangle depending on the following situations:
1) Given the coordinates of the 3 points
2) Given 3 line segments (s-s-s)
3) Given 2 line segments and the angle in between (s-a-s)
4) Given 2 line segments and the angle opposite to the longer one (a-s-S)
5) Given 2 angles and the line segment between them(a-s-a)

The cases 2) to 5) correspond to the sentences of congruence.

The calculated triangle will be drawn in a 2d-coordinate-system

Numerous options show up in a menu that appears when you tap on a line segment.
You may choose between the following objects:
- Mid Perpendicular
- Median
- Bisectrix of angle
- Height
- Incircle
- Circumcircle
- Thales circle
- Squares over sides
If selected, the objects are shown in the graphic.