Minecoins buy skins, worlds and add-ons in the Minecraft Marketplace. Here is how they work across devices.
Minecoins are the currency of the Minecraft Marketplace in Minecraft Bedrock Edition. You use them for skins, texture packs, worlds and add-ons made by creators.
Minecoins are linked to your Microsoft account. On most Bedrock platforms you can use them as long as you sign in with the same Microsoft account.
Use the same Microsoft account everywhere so your coins and purchases follow you.