my idea is snapping center map cursor to vertex (point,polygon,line), when map cursor be near from any vertex?
Hi Todd, if you are creating a point/line/polygon, this feature already exists (if I have understood your suggestion correctly). After clicking "+" to create a new object and then selecting the object type (point, line, polygon), at the top of the screen the selected object type will be mentioned on the top left and magnet symbol will appear on the top right. Tap the magnet so that it is coloured green. Now any points or vertices created using the screen centre crosshair that are close to existing points/vertices will snap to them. The snapping tolerance is roughly the length of each arm of teh crosshair i.e. imagine a circle with a radius the length of the crosshair. If there is an existing point/vertex within that imaginary crosshair circle, it will snap to it. If it doesn't them just select "undo", move the crosshair a little closer and try again.