Third-party Twitter services are no longer allowed under Elon Musk's Twitter 2.0.

The microblogging company quietly updated its developer rules that effectively banned its third-party apps from using its API due to them being a substitute or similar product to Twitter Applications.

Many developers of Twitter's third-party apps like Twitterbot, Twitterific, and Echofon noticed that users couldn't log in to their apps or access Twitter feeds in mid-January, while some remain unaffected.

Twitter New Developer Rules Details

Twitter added a new clause to its third-party developer rules that effectively banned them from using the company's API. According to this clause, third-party apps are prohibited from using or accessing the Licensed Materials it provides to "create or attempt to create a substitute or similar service or product to the Twitter Applications."

The company defined "Twitter Applications" as its consumer-facing products, services, applications, websites, web pages, platforms, and other offerings. These also include those offered through Twitter's webpage and Twitter's mobile applications without limitation.

A quick search using the Wayback Machine indicates that Twitter quietly added this clause to its developer rules on Jan. 18.

As expected, Twitter's third-party developers did not receive the news with welcome arms, though they did suspect this would happen.

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Developers' Reaction To The Ban

As expected, Twitter's third-party developers did not receive the news with welcome arms, though they did suspect this would happen. According to The Verge, several commentators and developers pointed out the lack of clarity about what rules they actually broke, and that their apps had been operating under Twitter's API for years before Elon Musk took over the company and started announcing plans to turn Twitter into an "everything app."

You may remember that Musk previously announced he is planning to turn Twitter into something like a bank with his idea of offering banking services on Twitter through a "High-yield money market account," debit cards, checks, and loans.

Ged Maheux, a co-founder of Twitterific developer The Iconfactory, said in a blog post that the developers have been respectful of Twitter's API rules, as published, for the past 16 years. He also added that they do not know that these rules recently changed or what those changes might be.

Craig Hockenberry, principal at Iconfactory, agrees with Maheux, saying that Twitter didn't give any advance notice to its creators and that no one is explaining what happened recently.

"We have no chance to thank customers who have been with us for over a decade," Hockenberry added.

Twitter, however, does not agree with Maheux and Hockenberry's views. The company previously said it was enforcing its long-standing API rules on a Jan. 18 tweet.

However, this tweet doesn't align with its history, as Twitterrific, a popular Twitter thid-party app, was created before the company had a native iOS app of its own.

Engadget reports that Twitter no longer has a communications team to announce these changes, and that most of its staff that worked on its developer platform were fired during the company'a mass layoffds in late 2022.

Related Article: Twitter May Be Intentionally Killing Off Third-Party Apps