The name MP4 player is a marketing term for portable media players that comply with certain standards and formats. The name itself is a misnomer, since most MP4 players are incompatible with the MPEG-4 Part 14 or the .mp4 container format. Instead, the term symbolizes their status as successors of MP3 players. In this sense, in some markets like Brazil, any new function added to a given media player is followed by an increase in the number, despite there being no corresponding MPEG-5 standard (as of 2010, the current standard, still being developed, is MPEG-4).

The MTV video format (no relation to the cable network) consists of a 512-byte file header that operates by displaying a series of raw image frames during MP3 playback. During this process, audio frames are passed to the chipset's decoder, while the memory pointer of the display's hardware is adjusted to the next image within the video stream. This method does not require additional hardware for decoding, though it will lead to a higher amount of memory consumption. For that reason, the storage capacity of an MP4 player is effectively less than that of a player that decompresses files on the fly.