Desktop application-level virtualizations

Flatpak, AppImage, Snaps, and other similar technologies also provide isolation and packaging for single-application level containers, but unlike Docker, all of them target the deployment of desktop applications and do not have as precise control over the container life cycle (that is starting, stopping, forced termination, and so on) nor do they generally provide layered images. Instead, most of these tools have nice wrapper Graphical User Interfaces (GUIs) and provide a significantly better workflow for installing, running, and updating desktop applications. While most have large overlaps with Docker due to the same underlying reliance on mentioned cgroups and namespaces, these application-level virtualization platforms do not traditionally handle server applications (applications that run without UI components) and vice versa. Since this field is still young and the space they all cover is relatively small, you can probably expect consolidations and cross-overs so in this case it would be either for Docker to enter the desktop application delivery space and/or for one or more of these competing technologies to try to support server applications.