It is legal to download free MP3 ringtones as long as they are legally available and you are using them for personal use. Yes, most phones allow you to assign specific ringtones to your contacts to quickly identify them. You can usually delete a downloaded ringtone by going to your phone's sound settings and navigating to the list of available ringtones. The quality of free MP3 ringtones may vary depending on the source. It is better to download from reputable websites or apps for better sound quality.