Keyboard assembly with interchangeable keys and method of operating the same

A keyboard assembly for a handheld device, comprising:

• a housing having a first section and a second section;
• a plurality of slots formed on the first section;
• a printed circuit board (PCB) disposed between the first and second sections;
• a key mat sandwiched between the first section and the PCB, the key mat having a plurality of fixed keys and a plurality of interchangeable keys, each key protruding from a corresponding slot on the first section, wherein each of the interchangeable keys comprises a key cover and a key base,
• wherein the plurality of interchangeable keys, each has a plurality of pins extending from each interchangeable key towards the PCB configured to provide each interchangeable key with a unique identity, such that when each interchangeable key is replaced onto another slot on the first section, the unique identity remains with the interchangeable key, and wherein the plurality of pins are configured to be selectively coated with a conductive material.