Select Video editor.
You can combine pictures and videos with sounds, effects, and text, and easily turn them into short movies or slide shows.
The following codecs and file formats are supported: MPEG–4, H.263, H.263 BL, WMV, JPEG, PNG, BMP, GIF, MP3, AAC/AAC+/eAAC+, WAV, and AMR‑NB/AMR‑WB.
Save the sound files that you want to use in a movie to the Sound files folder on your phone.
You cannot add a DRM protected sound file to a movie.