The legality of downloading free MP3 telecharger sonnerie depends on the source you are downloading them from. Be sure to use reputable websites and apps that offer free ringtones legally.<br /><br />Free MP3 ringtones usually work on most phones that support MP3 files as ringtone formats. However, it is best to check your phone's compatibility before downloading a ringtone.<br /><br />Yes, you can customize the length of your MP3 ringtones using audio editing apps like Audacity. You can trim and adjust the duration of the song to match your preferences.