Questions, bugs, or feature requests? Email tmdals999@gmail.com and I'll get back to you.
Photograph one part at a time, on a plain background that contrasts with its color, in good light. BrickDex always shows several candidates — tap the right one. If none match, use Search to find it by number or name. Choosing a different candidate also helps the recognition engine improve.
The recognition engine uses BrickLink part numbers, and a few of them (mostly older molds) have no entry in the Rebrickable catalog BrickDex is built on. You'll still see the part's name and picture, and you can look it up on BrickLink by that number.
About one part in ten — stickers, gears, and rarely used pieces — has no photo in the catalog yet. A silhouette is shown instead. Recognition is not affected.
Scanning needs an internet connection, because recognition happens on a remote service. Everything else — your collection, search, the dex, and buildable sets — works offline.
The core dex is the 500 most-used part types across all LEGO sets. Each part you add to your collection lights up its entry, and a rarity tier (Common through Unique) is derived from how many sets the part has appeared in.
Open Settings → Restore purchases inside the app. Make sure you're signed in with the same Apple Account or Google account you purchased with.
Open My parts and tap Export. You can save a CSV file or a BrickLink wanted-list XML that can be uploaded directly to BrickLink. Export is part of BrickDex Pro.
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