3GP to MP3 Converter
Full user review
"Perfect Converter for 3GPP to MP3"
Select the file. Select the destination. Give it a name (don't forget to add ".mp3" extension). Hit the button. Boom. You're done. Perfect.
The only way it could be made better is if it could do multiple files at once and if it automatically added the mp3 extension.
If you're converting one or two 3GPP files to MP3 at a time, this is your app.