Amazon shut down their API for this and doesn’t provide any third-party integrations, but they clearly don’t give a toss about their shopping list feature in their app—it barely works and loses state constantly. But we like using the photo frame Alexa to track stuff. So I finally had Opus 5.5 figure out a way to make two-way sync work, which has been working well! It needs an always-on Mac, but then you can add/edit/check off on either side and it stays in sync.