Ringtone melodies (chaku-mero) are music played for incoming calls. Early mobile phones only produced simple electronic tones, but polyphonic ringtones emerged around 1996, allowing custom song settings. With i-mode, ringtone downloads became a massive business.
Evolution was remarkable: from monophonic to 4, 16, and 40-voice polyphony. "Chaku-uta" (2002) played original vocals, and "Chaku-uta Full" (2004) offered complete songs at 200-400 yen each. Annual chaku-uta sales peaked at approximately 90 billion yen in 2008.
Smartphone adoption rapidly killed the ringtone business. iTunes and Spotify became dominant, and interest in ringtone customization faded. Modern smartphones typically use preinstalled tones or music files set as ringtones.
Culturally, ringtones transformed phones into self-expression tools. Ringtone choice expressed individuality, continuing the pager wordplay tradition of "mobile self-expression." See telephone evolution for mobile culture history.