There are new expressions in the touch event that you also might find useful.
AngleAt(index)
AngleForID(id)
Get the angle of motion of a specific touch in degrees by its zero-based index or unique ID. A touch must be moving across the device screen for this expression to contain a useful value.
SpeedAt(index)
SpeedForID(id)
Get the speed of a specific touch by its zero-based index or unique ID. Touch speed is measured in canvas pixels per second, so is not affected by scaling the display.
AngleAt(index)
AngleForID(id)
Get the angle of motion of a specific touch in degrees by its zero-based index or unique ID. A touch must be moving across the device screen for this expression to contain a useful value.
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