For outdoor use

Electronic Digital Theodolite
The lightest & smallest theodolites TEO-100

Surveying Compasses
Laser distance meter-tipped Pocket Compass PocoRay
Surveying Compasses LS/S Series

Forester's Caliper
Forester's Caliper Ushikata Forester's Caliper

For indoor use

Area Curvimeter
Simplified Area and Length of line Measurements X-PLAN dIII series
The low-cost model X-PLAN F.C series
The best digital planimeter X-PLAN F series

Software

Software for X-PLAN series
For F / F.C series Software for X-PLAN