The ornamental design for a handheldsensordevice, as shown and described.
FIG. 1 is a front, left, and top perspective view of a handheld sensor device embodying the new design;
FIG. 2 is a rear, left, bottom perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a right side view thereof;
FIG. 6 is a left side view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
The broken lines in the figures are shown for the purpose of illustrating portions of the handheld sensor device and/or environmental matter and form no part of the claimed design.