RealCADD and iPocket Draw

Sorry, but I didn’t understand how Zoom command works

There is the tool "Zoom" to zoom in by drawing a rectangle.
A single tap with the tool, reset to zoom 1x centred on the clic.
With Arrow tool, 3x taps reset the zoom 1x and delta x and delta y to zero (no scroll).
With Arrow tool, 4x taps to do a zoom all objects.
And as other app on iPad, you can use the pinch gesture to zoom in and out.

I can't work with the zoom command.

It’s a mess

Drawing a zoom rectangle works, but

I can’t go back at the same proportion before the zoom rectangle and in the same position

When pinch in or pinch out with finger, often active selection of objects or drawing of random lines

Zoom in and zoom out would be an easy operation and very precise

solved!