Minecraft worlds on mobile (Bedrock Edition on iOS/Android) do not automatically sync between devices through a Microsoft or Xbox account. Signing in with the same Microsoft account lets the game sync things like achievements and marketplace purchases, but local worlds remain stored on each device.
To move worlds between two mobile devices, a manual transfer is required (for example, backing up the world folder from one device and restoring it on the other, or temporarily hosting a world on one device and joining it from the other, then using in‑game copy/export features if available). There is no Microsoft or Xbox account setting that enables automatic cloud sync of mobile worlds.
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