Developers working on client applications that replicate Twitter.com's basic user functionality should turn their efforts elsewhere, because the company doesn't want any more such apps on the market.
Moreover, developers of existing client applications should brace for stricter enforcement of terms and conditions, as Twitter strives to make the overall user experience more uniform and of higher quality.
That was the message Ryan Sarver, from Twitter's application development team, relayed over the weekend on an official Twitter discussion forum for developers.
"Developers have told us that they'd like more guidance from us about the best opportunities to build on Twitter. More specifically, developers ask us if they should build client apps that mimic or reproduce the mainstream Twitter consumer client experience. The answer is no," Sarver wrote in a post titled "Consistency and ecosystem opportunities."
"If you are an existing developer of client apps, you can continue to serve your user base, but we will be holding you to high standards to ensure you do not violate users' privacy, that you provide consistency in the user experience, and that you rigorously adhere to all areas of our Terms of Service," he added.
Twitter has also modified its developer terms accordingly and provided more details about this topic in that document.
Responses to Sarver's post have so far been mostly negative.
"All third party Twitter developers, no matter what they make, are now walking on eggshells, constantly at risk of offending Twitter's ideas of how users should interact with Twitter," wrote one developer, echoing similar sentiments from others commenting on the discussion thread.
Tensions between Twitter and its community of third-party developers have been worsening over the past 12 to 15 months, when Twitter started taking a more active role in building out its previously sparse menu of native features.
For the first four years or so of its existence, Twitter relied heavily on -- and encouraged -- external developers to provide extra functionality around its bare-bones microblogging service.
During that time, Twitter, founded in 2006, had its hands full keeping up with the basics of running the company, such as maintaining the site up and available, a notorious struggle for years.
Thus, developers have created hundreds of thousands of applications for Twitter, including desktop clients, mobile interfaces, search engines, photo sharing tools, monitoring and analytics software and profile customization tools.
Many of these developers, which range from individual freelancers to large outfits, have built businesses of various sizes around their Twitter applications.
But starting in late 2009 and very clearly ahead of its Chirp developer conference a year ago, Twitter, having grown its staff and business significantly, has made it clear that it intends to provide by itself or in exclusive partnerships whatever functionality it considers of core importance to the Twitter user experience.
That now includes official Twitter applications for the iPhone, BlackBerry, iPad, Windows Phone and Android devices, for example. "As a result, the top five ways that people access Twitter are official Twitter apps. Still, our user research shows that consumers continue to be confused by the different ways that a fractured landscape of third-party Twitter clients display tweets and let users interact with core Twitter functions," Sarver wrote in his post.
So over the past year, Twitter has become a competitor for some of its external developers.
As examples of developers who are taking advantage of existing opportunities, Sarver cited SocialFlow's publisher tools, Klout's application which crunches Twitter data to generate individual reputation scores and HootSuite and Seesmic, which let businesses monitor their brand mentions on Twitter and act accordingly.