測量野帳 SIMA｜座標計算・野帳

This app was created to eliminate the anxiety of SIMA files crashing the moment they're opened.

SIMA Survey Notebook is a coordinate calculation app for Japanese surveying professionals that reliably reads and writes the SIMA common format (.sim), and handles everything from reverse calculations, coordinate area calculations, traverses, forward intersections, and instrument-level field notebooks all on a single smartphone. It works completely offline.

【SIMA Never Crashes】
- Even if there are corrupted records during import, the app will never crash. It skips unreadable lines and reports the number of skipped records on the spot.

- Automatically detects Shift-JIS / UTF-8 character encoding. It can open files exported by Japanese surveying software directly.

- Ignores records other than coordinates, such as plot sizes (D00/B01), and imports only the coordinates.

[Comprehensive Calculations for Field Use]
• Inverse Calculation (Between Two Points) — Distance and direction angle in degrees, minutes, and seconds
• Coordinate Area (Double Area Method) — Calculates area from selected coordinates
• Radiation Calculation (Traverse) — New point coordinates from known point + direction angle + distance
• Forward Intersection (Intersection Method) — Unknown point coordinates from the direction angles of two known points
• Instrument Height Leveling Field Book — From BS/FS/instrument height to ground height GH, measurement (ΣBS−ΣFS), and difference

[Correctly Supports the Japanese Coordinate System]
• Adheres to the conventions of the plane rectangular coordinate system with X = North and Y = East.
• Angle input and output in degrees, minutes, and seconds (DMS).

[Designed for Field Use]
• Sleep prevention prevents the screen from turning off during use.
• All entered coordinates are saved only within the device. Atomic writing ensures that the coordinate list is not lost even if the device crashes.
• No account required. No ads. Entered coordinates and calculation data are never sent externally via communication. [One-time purchase]
The free version allows you to manually input coordinates (unlimited), perform inverse calculations, calculate coordinate area, and preview SIMA data (up to 50 points). Features have not been removed to make it inconvenient.

The Pro version (one-time purchase) is a one-time payment that unlocks unlimited SIMA data import and export, as well as traverse, forward intersection, and instrument-level field notebook functions. It is not a subscription service. There are no ads or additional charges for features.

*This app is an auxiliary tool for surveying calculations. Please always verify the results using the proper procedures.