Thanks! I was missing the right permission, thank you very much
Topic summary
Main issue: A Shopify POS embedded app using App Bridge could not dispatch or subscribe to Cart actions; featuresAvailable returned false for all Cart capabilities, so adding a line item failed on Android POS v3.53.0.
Technical context: Shopify App Bridge is a JavaScript SDK for embedded apps; Cart actions (e.g., ADD_LINE_ITEM, UPDATE) modify the POS cart; featuresAvailable checks action support; OAuth scopes like write_orders control permissions.
Resolution: A respondent advised starting with a minimal ADD_LINE_ITEM action and ensuring the app has the necessary scope (write_orders). The original poster confirmed the problem was missing permission and was resolved after correcting it.
Follow-ups: Another participant requested details on the fix beyond “missing the right permission,” but no further specifics were provided. A separate user reported not seeing their app link on the POS cart edit screen and asked if interactive code is required to apply discounts based on customer tags; this remains unanswered.
Status: Cart issue resolved via permissions; later questions about app link visibility and discount implementation are open. A screenshot is central to the unresolved POS link visibility issue.