It's not clear what happens when a user who doesn't have an account with WhatsApp taps on WhatsApp shortcut button. Facebook may have plans to further boost the user base of WhatsApp, which is still struggling to gain traction in the United States and other Western markets. The company may have plans to bring additional WhatsApp integrations before rolling it out to all, based on the response it sees.
Facebook acquired WhatsApp in 2014 and has since been exploring ways to make the two services benefit from each other. Last year, the company started to use some user details on WhatsApp for ads and other purposes. The move invited criticism from privacy enthusiasts who pointed out that WhatsApp had said earlier it would never share any user data with Facebook.
Regardless of the integration Facebook, used by over 2 billion people, has in mind for WhatsApp, used by more than 1.2 billion people, it would want to ensure that it is not using its market dominance for competitive advantage. As those moves tend not to bode with regulators, especially aggressive EU watchdog.