Hand-held device comprising sensor unit, for characterizing a treated substrate

Handheld device for manually actuating by a user, wherein the handheld device comprises:

• a processing unit which is configured for processing an underground;
• a sensor unit which is configured for detecting sensor data which are indicative for a condition of the underground, before, during, and/or after processing the underground;
• a determination unit which is configured for determining an information which is indicative for the condition of the underground, based on the sensor data;
• and
• a user interface for outputting an operation proposal for a use of a dowel and/or an attachment element for the underground, based on the determined information which is indicative for the condition of the underground.