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List Mode is for building the list — add, edit, tick things off in advance. Shopping Mode is for while you're actually in-store: tapping an item finds it on the map (in-store retailers) or opens its online order link, instead of editing it.
The 📷 button scans a product barcode and looks it up on Open Food Facts, adding it pre-tagged with a colour-coded health chip (green/amber/red) from its nutrition grade. No barcode, or the product isn't found? Add it by name and set the health tag manually from the edit screen.
Filters the list down to items you personally added — handy once a few people share the same list and it gets long. Items nobody explicitly added (from before this was tracked) count as the household owner's by convention.
The small coloured circle on an item shows who added it — always the same colour for the same person, across every dooo app.
Changes reach every signed-in device automatically. If something looks stale, pull to refresh or reopen the app.