It’s a move that has been coming for some while, but today Twitter finally confirmed that it has “retired” API v1 and is transitioning to its new API v1.1.

In practical terms, that is the final bell for a number of Twitter apps which will bite the dust, including a series of (Twitter-owned) TweetDeck for iOS, Android and Adobe AIR, SilverBird and DestroyTwitter.

Most popular apps have heeded the many warnings from Twitter, and transitioned to API v1.1 to retain their access to Twitter but some independent developers have already called it a day, due to usage restrictions that were imposed on smaller apps.

For example, TweetLanes developer Chris Lacy opted to open source the app last year, after he conceded that restrictions placed on the API — which caps it at 100,000 user tokens — meant monetization was “no longer feasible”.

Twitter actually extended the life of API v1 by one month — after originally announcing May 7 as the shutdown date — but that was to enable it to run more “blackout” tests and other trials to ensure stability as API v1.1 takes over.

Back in March, it was announced that TweetDeck AIR and the iOS and Android apps would be killed off. TweetDeck for Mac and PC will stick around for now, and they will closely follow the feature updates that will debut on the Web and Chrome versions of the app. Those Web editions will be the primary TweetDeck experience, and will get rollouts of new Twitter features and updates first.

Twitter became prominent thanks to a range of third-party apps that extended the experience with additional features and support, however, as of around June 2012, the company began restricting developers and their apps. Primarily, the company began controlling its API more tightly, after introducing a series of features — including Twitter cards and enhanced multimedia support — which are key to its advertising offering, and core to its revenue model.

Today’s retirement is unlikely to affect any popular apps — since developers have been well aware of the impending transition for some time, and can largely continue affected — but it is a clear milestone of Twitter’s once open ecosystem becoming more restricted.

It isn’t too late for developers to migrate their apps to the new API, as the post from Twitter’s developer blog explains:

Based on the blackout tests and looking at the numbers, we can see that the vast majority of applications have transitioned to API v1.1. If you still have not updated your app and you want people to be able to continue using it, it’s not too late! Documentation is available here.

Additionally, here are other resources that we’ve pulled together to help make this transition more smooth:

Twitter looks like it is having some embarrassing problems of its own, however. We found its own search engine was not working due to API issues.

twitter api Twitter retires API v1, finally killing off TweetDeck for iOS, Android, AIR and other apps

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