Convert MP4 to AMR

If you need to extract an audio track in Adaptive Multi-Rate Codec format (AMR) from an MP4 movie, there are a number of media editing programs and converters that can reliably do that (.mp4 to .amr conversion).

Choose one of the many available tools, like FormatFactory or Freemake Video Converter, which are perfectly capable of importing MP4 videos and re-saving their extracted audio track in AMR format.