The invention relates to a handheld device for the local puncturing of a human or an animal skin, in particular for the introduction of an active substance or for the application of a tattoo or a permanent make-up, comprising a drive unit which is configured so as to produce a repetitive drive movement, and a needle unit which comprises a needle device and is configured so as to couple to the drive unit in such a manner that the repetitive drive movement for the extension and retraction of the needle device can be coupled into the latter, said drive unit having formed on it a displaceable actuating element which is functionally coupled to a needle connection device, and said needle unit having formed on it a functional member which is assigned to the actuating element, said actuating element and said functional member being configured so as to move the actuating element from a first displacement position to a second displacement position by means of the assigned functional member when coupling the needle unit to the drive unit, thus moving the needle connection device to a coupling position in which the needle device can be coupled to the needle connection device for purposes of operation. Furthermore, the invention relates to a method for coupling a needle unit to a drive unit on a handheld device, a drive unit for a handheld device as well as a needle unit for a handheld device.
