Snap/Align Tool and Tolerance Setting

I cannot count the amount of times i was frustrated about two parts/lines/points being very very close to each other but not getting them to Align. A “magnet” tool that fuses the selected point/lines together would be very helpfull. OR a tolerance setting that would goup them automatically if they are for example only 0.1 mm apart from each other. (like a 3 dimensional grid the point would stuck to)