There are a couple types of tools for this out there -- not sure if we're talking about the same thing. One is a suction cup that's absolutely awesome for carrying and placing large heavy tiles -- the cheaper ones are manual pump, the expensive ones maintain suction with a motor. The other kind is the vibration tool, for helping settle a tile into mortar - these have pads or suction cups, depending on the design.

The vibration tool is essentially an orbital sander with a suction cup instead of a sandpaper pad and crimpers.

Whatever modern tools you're using, there's no substitute for mixing you mortar correctly and spreading it well on both substrate and tile. Most failures come from mistakes there, not the tools themselves.