Twitter Blue, the social media platform’s subscription service, which allows users to buy a blue verification badge for the first time, has gone live in the UK.
Twitter users on Apple’s iOS can now sign up and pay for the service, which will give them the blue-tick badge next to their profile name on the platform.
The company said the service would expand to Android and the web version of the app for users in due course, but Twitter's new owner Elon Musk continues to face criticism over the controversial change.
Here's everything you need to know about Twitter Blue.
What is Twitter Blue?
Twitter Blue is Mr Musk's solution to weeding out spam and fake accounts. He's argued it will have this effect because such accounts will not be willing to pay to get traction on the site.
Twitter Blue is also set to add a feature that will promote replies to tweets from verified accounts as a way of rooting out those not verified on the site, as part of a range of other perks labelled as “coming soon” to the subscription.
But critics have warned it will enable a new wave of misinformation as bad actors sign up for the badge and then pose as public figures to spread false information.
In the US, accounts pretending to be President Joe Biden and gaming giant Nintendo, sharing offensive material, have already been spotted.
Twitter has pledged to stamp out any fake or misleading use of the system and says it will not allow users to change their display name after receiving a badge.
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How much does Twitter Blue cost and how can you get a badge?
Anyone who wishes to have a blue verification badge next to their handle can do so by paying a £6.99 monthly subscription fee.
What is different about Twitter Blue?
Twitter’s online help pages say the definition of the blue checkmark is "changing" as part of the update.
"Until now, Twitter used the blue checkmark to indicate active, notable, and authentic accounts of public interest that Twitter had independently verified based on certain requirements," the company said.
"Now the blue checkmark may mean two different things: either that an account was verified under the previous verification criteria [active, notable, and authentic], or that the account has an active subscription to Twitter Blue.
"Accounts that receive the blue checkmark as part of a Twitter Blue subscription will not undergo review to confirm that they meet the active, notable and authentic criteria that was used in the previous process."
It adds that the changes are designed to "help reduce fake, untrustworthy accounts, and promote higher quality Twitter".
What will happen to accounts which are already verified?
For now, accounts verified under the old system are allowed to keep their own blue badges.
Which countries have access to Twitter Blue?
The new system has gone live for users on Apple's iOS in the US, Canada, Australia and New Zealand, alongside the UK.