Facebook has begun prompting users to download its Messenger app in a bid to move the instant message function off the site for iPhone and Android users.

The messenger app, which was created in 2011 but not made compulsory at the time, is now being pushed to members who use the site on their mobile phone.

The forced adoption of the program has increased criticism of the app’s design and privacy settings.

For Android users in particular, the app requires users to agree to stringent policies like “call phone numbers without your intervention,” and “use the camera at any time without your permission,” according to The Wall Street Journal.

Facebook has responded to critics by blaming the privacy issues on the strict permissions policies of all Android phones, insisting in a Help Centre article that the official language used “doesn’t necessarily reflect” the way the Messenger app and other apps use the phone.

However, tech savvy individuals still fear the infiltration of their devices. A blog post for Huffington Post warned users that in the fine print, Facebook demanded the ability to change network connectivity, send SMS messages, record audio, use the camera and access contacts data amongst other measures.

According to the company, the app is still in development.

“Our goal is to focus development efforts on making Messenger the best mobile messaging experience possible and avoid the confusion of having separate Facebook mobile messaging experiences,” a Facebook representative wrote in an email to Huffington Post.

“Messenger is used by more than 200 million people every month, and we’ll keep working to make it an even more engaging way to connect with people.”