Thumb-triggered wearable device and system

An apparatus comprising:

• an application specific module for wearing atop the dorsal of a user's preferred hand, the module having an anterior side and a ventral side worn respectively oriented distally and proximally with respect to the user, the ventral near anterior of the module fully containing a transverse bilaterally symmetric channel having openings on each lateral side of the module;
• a readily user attachable and user detachable thumb trigger assembly comprising a channel-plug end, an end having a trigger button, and an intermediate portion mechanically and electrically connecting the channel-plug end and the trigger button end;
• wherein the thumb trigger assembly is removably mechanically and electrically mounted in the channel via the channel-plug end in a selected one of a left-handed and a right-handed reversible orientation in accordance with the user's preference, the mounted thumb trigger assembly protruding from the module only through the lateral side channel opening proximate to the user's preferred hand forefinger side;
• wherein the module with mounted thumb trigger assembly is removably positionable via removable attachment atop the user's preferred hand;
• wherein a thumb relative quasi static position of the trigger button is customizable for exercising the trigger button by the user's thumb to cause a module state change;
• and
• wherein the intermediate portion is a cable and the trigger button end further comprises a magnet to removably hold the trigger button end against a forefinger worn ferromagnetic material to operatively hold the thumb relative position.