Abstract: A computer-implemented method includes allowing a first user to initiate a design of an image product on a first device, allowing the design of the image product to be shared to mobile devices operated by second users, receiving personalized messages comprising a plurality of pixels from the first user or the second users by a network-based image service system, storing personalized messages from the first user or the second users in different layers at a data center in the network-based image service system, concurrently broadcasting changes in values of the pixels to the first device and the mobile devices to allow an overlay of the personalized messages on the first device or the mobile devices, and incorporating the personalized messages into the design of the image product by the network-based image service system.