Abstract: Provided are methods, computer programs and apparatus supporting cooperative updating of software, firmware and other data. A first device is able to obtain program and data updates that are required by other devices, and to do this altruistically even if the updates are not required by the first device. The updates obtained by the first device are saved in cache storage until they can be transferred to the other devices that require update support. A set of devices form a Data Sharing Group and hold information representing update requirements of the other group members. Altruistic obtaining and caching of updates can be especially beneficial for devices that have very limited network access—for example devices that have only intermittent network connectivity, or have low bandwidth or low security network connections.