Hi, @carlamac
We would like to welcome you to the king community. Thank you so much for being willing to joining.
In the case of Android and I-Phone, your collected booster is stored in a specific location in the application. This stored booster can not be synced with the server, because the game studio still does not have this process.You will not be able to transfer the boosters to another device, you will lose the complete booster for app uninstalling or crashing. and the boosters are not refundable.
Welcome to the Candy Crush Saga Community
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