K.109.3gp -

Sometimes requires a codec pack, but usually works.

It was heavily used in the early-to-mid 2000s for storing low-resolution, low-filesize videos on phones, often referred to as "3G video" 1. k.109.3gp

These files are optimized for small storage space and low bandwidth, meaning they are often lower quality compared to modern MP4 files. Sometimes requires a codec pack, but usually works

This container format was designed to allow mobile phones to record, store, and transmit audio and video files over high-speed wireless networks 1 . Sometimes requires a codec pack