How a given service chooses to present their video on any given device, and the accompanying elements of the service's user interface, is a very important question, but one that sometimes has political, as well as technical overtones. In general, downloadable apps are used for commercial video services on mobile devices, tablets and TVs, while desktop/laptop computers often use a browser environment. There is a lot of debate over the merits of the two approaches in terms of user experience, considering startup time, service latency and device efficiency for example. The standardized video format of MPEG-DASH was originally defined around the need for in browser consumption, although the usage profile is very much a moving target at the present time.