A tweet sent today from the official Gmail Twitter account says that Google's email platform now has 1.5 billion active users. That is up 33% from the 1 billion active users that Gmail reported 34 months ago in February, 2016. With a world population of 7.53 billion, there is one Gmail account open for every five people on the planet. Keep in mind that several subscribers do have more than one account.
Gmail started on the desktop in April 2004 as a limited beta release (which ended by July, 2009). A java version became available to mobile phones in 2006. By 2012, Gmail had 425 million active users, a figure that more than doubled to 900 million by 2015. 75% of them were using the service on a mobile phone.
Today's tweet includes a GIF that shows a message being typed on the Gmail desktop version that reads, "We just wanted to say thanks to each and every one of you," and is signed "Love, the Gmail team." If you are not one of the 1.5 billion Gmail users, you can install the app on your phone by clicking on the appropriate link: (Android|iOS).