PhotoMOB is a GIS toolbox automating the tasks to perform a spatial-temporal quantification of grain size distribution, bed stability and fractional mobility from photos of gravel bed river after hydrological events. Grain are classified as identical (i.e., stationary) or different (i.e., mobile/turned out). The grain size distributions from the photos can be extracted in the form Area-by-Number or Grid-by-Number and are compatible with measurements obtained via other methods as pebble-count. This folder contains data related to both papers in following subfolders: 1_PhotoMOB_part1_Data: data used for error assessment of grains characterisation Grain dataset collected in the field (1_Real),with measurement of the axes (a, b and c) measured using the Pebble-Box, measurement of the weight, estimation of the position of the grains on the surface of the bed. Grain dataset digitised manually and identified automatically by the supervised and automated PhotoMOB procedures as well as for Basegrain free stand-alone tool from Detert and Weitbrecht (2013) and Sedimetrics Digital Gravelometer from Graham (2005a, 2005b). 2_PhotoMOB_part2_Data: data used for error assessment of grain dynamics 3_Example_Data_ready_to_PhotoMOB_Extractor_App: This corresponds to a dataset of 3 hydrological events processed by the PhotoMOB GIS protocol (Part 1 +Part 2). These data are available as an example to be used in the PhotoMOB Extractor application (https://shiny.fannyville.com/photomob_extractor/) to obtain an overview of the output available from these data.