As of 2023, the number 1 messaging app varies by region and demographics. In some countries, WhatsApp may be the most popular, while in others, it could be WeChat or Line. However, globally, WhatsApp is one of the most widely used messaging apps due to its ease of use, end-to-end encryption, and widespread availability. Other popular messaging apps include Facebook Messenger, Telegram, and iMessage. Ultimately, the number 1 messaging app can vary depending on a variety of factors, including user preference, geographic location, and personal needs.