Facebook Inc. said Monday 500 million people regularly use its Messenger app. In a controversial move during the summer, it required users to download Messenger in addition to its main app to continue using the chat service on smartphones, but that seems to have had little effect on the social network's mobile reach.

Facebook has more than doubled the number of monthly active users it had on the chat app in April when it had reached the 200 million mark, despite angering a few users in the process. Messenger is now chasing the total number of monthly active users for WhatsApp (600 million), which it acquired earlier this year. The announcement comes days after founder and CEO Mark Zuckerberg addressed the “friction” the forced installation created with users during a Q&A with users.

“Messaging is one of the things that people do more than social networking,” he said. "Even though it was a short-term, painful thing ... we knew that we could never deliver a quality experience inside as a tab on the main app.”

Facebook is also looking to move into mobile payments in its messaging app. Not content with its better-than-expected growth in mobile advertising, the social network may be planning to allow users to exchange money on Messenger much like they would transfer a photo.

Code was found embedded within the iOS version of the app that allows users to add debit and PIN codes to Messenger to allow them to send money. Facebook, however, will likely take some time to establish “trust” with its users first, which Zuckerberg admitted faltered when it removed Messenger features from the main app.