The ornamental design for a wearableposturedetectiondevice, as shown and described.
FIG. 1 is a top perspective view of a wearable device showing our new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines in the drawings depict portions of the wearable posture detection device in which the design is embodied that form no part of the claimed design.