TopoDroid has an in-app user manual in English.
These docs are rather old and describe old version of the app.
User manuals
The latest TopoDroid user manual: https://github.com/marcocorvi/topodroid/blob/master/manual.pdf
Older TopoDroid versions user manuals:
V. 4.1 (Aug. 2018) TopoDroid user manual
V. 2.2.4 User Manual French - G. Chardin
V. 2.7 User Manual Spanish - M. Guerrero
V. 3.? Guia Rapido Portuguese - R. Severo
V. 4.1.1 (Oct. 2018) Introduction to TopoDroid
V. 4.1.1 (Jan. 2019) Manuel Utilisateur French - D. Ros
V. 4.1.4 German User Manual - M. Miehle
V. 6.3.30 Parsian user manual - F. Saeed
Topics
Web page about TopoDroid in french: http://souterweb.free.fr/boitaoutils/topographie/pages/topodroid.htm
DistoX2 calibration with TopoDroid: http://www.gzluna.com/cave/distocalibnew.html
Survey accuracy and the DistoX
TopoDroid activity levels - v 3.4.0f
TopoDroid folders and files
TopoDroid shapefile export and QGIS - v. 4.1.2
Working in TopoDroid for Therion - dec. 2018 -
Sketch extended profile - june 2019 - v. 4.1.3z
DistoX and TopoDroid - Calibration, precision, accuracy (March 2020)
Lectures
101-Introduction to TopoDroid (2016-09-02)
TopoDroidAndCSurvey (draft) - M. Mosca
Effective DistoX (Finale Ligure, 2017)
TopoDroid and cave surveying (Malaga, 2017)
Video Tutorials
TopoDroid Video Course mostly in Italian, some in English
Russian - A. Kozhenkov
https://www.youtube.com/channel/UC30R25_0XaVJqzVyXYmZ6-A
English - D. Bristol
Calibration data: https://youtu.be/Wpj1u4_K9PY
DistoX functions: https://youtu.be/OhQj18n6oFY
Survey data functions: https://youtu.be/5dJVP-A52NY
Sketching: htts://youtu.be/MviItVhmFWk
Presentations and Courses
2015-03-13 Bilbao - J. Guijarro Gonzales.
2016-02-24 CursoTopo - J. Pardo and M. Guerrero
2015-01-24 Levigliani: v. 2.4.1
2015-05-14 Corso DistoX2-TopoDroid - A. Righetto
2015-05-16 Rome: v. 2.5.4
2015-12-05 Martina Franca: v. 2.6
2016-05-28 Cueva del Puerto de Calasparra - J. G. Gonzalez
2016-06-16 Putignano: v. 3.1.1
2017-03-04 Casola Valsenio: v. 3.3.0
2017-03-18 Vicenza: v. 3.3.1
2017-03-05 Curso DistoX, TopoDroid, Therion - R. Severo
2017-11-02 Finale Ligure - EffectiveDistoX
2017-12-07 Malaga: EffectiveDistoX EffectiveSurveying, EffectiveSketching
2017-12-07 Malaga (Toposur): v. 3.4.3
2018-03-24 Trieste: version 4.0.0
2018-07-13 DistoX e TopoDroid - R. Zerbetto
2018-11-02 TopoDroid - Casola Valsenio v. 4.1.1
2024-05-30 TopoDroid - Balkan Cavers Camp
More
TopoLinux wiki has several pages on TopoDroid.
They are a bit old, but many things are still valid.
N.B. TopoLinux site has been archived Jan. 2016.
Any help producing documentation is appreciated.