Is there an app for iPhone/iPad to record the audio output streaming of any other app ?
I need to record the audio streamed from other apps and not the audio from the microphone.
Depending on the App on the Phone, there may be an export option for streamed files. An alternative might be to extract the desired file(s) from the iPhone backup on your computer.
Once you have the (large) stream file on your Mac (?), you can extract the desired tracks from the file. For lossless MP3 editing you might want to try Rogue Amoeba’s Fission or Macsome Audio Editor (free).