Currently, appsheet users cannot select multiples images / multiple files at once.
What I suggest ?
For images :
Create an 'Collection of images' table > that we can add the same way as current 'collection of files'
Add a column type "ImageList" (in column parameters, set the collection table)
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When User select multiple images from his gallery and save, it will automatically add them to the collection of images table. This table column are important as we need to reference the new images from anywhere in the app. To do so, automatically fill a "ReferenceTable" column and "RefRowID". Optionnaly, this can be setted up in the "ImageList" column parameters.
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+ Enable drag & drop on desktop.