The predominance of these two main email customers illustrates the predominance of mobile email openings: in December 2018, mobile email accounted for 43% of openings, while webmail accounted for 39%. In 2018, Gmail was the second most popular email client with 27% of openings, after the Apple iPhone email client with 29% of openings. By 2023, the number of email users worldwide will grow to 4.4 billion, up from 3.8 billion in 2018. By October 2018, Google’s email service had 1.5 billion active users worldwide. Despite the growth and importance of mobile messaging and chat applications, email remains a central part of everyday digital life. Although some 281 billion emails were sent and received daily in 2018, this number is expected to increase to more than 347 billion emails per day by 2022. When it comes to the most popular email customers, Apple and Google are constantly battling for first place. Statistical accounts: Access to all statistics. Contact us to access records, forecasts, studies and international data. Gmail consistently ranks among the top ten most popular smartphone applications in the U.S., reaching more than half of the U.S. mobile audience. You can view your favorite statistics by clicking on the star in the header.