Systems, methods and computer program products to perform an operation comprising receiving, by a first wearable device from a second wearable device via wireless data transmissions, an identifier of a first tile connected to a tile interface of the second wearable device, receiving, by the first wearable device from the second wearable device via wireless data transmissions, an identifier of a second tile connected to the tile interface of the second wearable device, and determining, based on a device data structure of the first wearable device storing tile state data for the first and second wearable devices, that the second tile was transferred from the first wearable device to the second wearable device.