As expected since Twitter photos was announced in June, the microblogging company has activated photo-tweeting from the Twitter API. With it, any application will be able to upload an image to Twitter's servers as part of a tweet. Adding images via the API follows Twitter's recent inclusion of the service for all users on its flagship website.

Official Twitter-hosted photos have been readable in tweets since shortly after the announcement, though only a small number of users could post them. As we wrote in June, a "type" field, which currently is only photos, suggests video may be on the way. Techcrunch also notes that the call to statuses/update_with_media may also suggest additional types of media, or may simply be an attempt to future-proof the API.

The announcement post notes that Twitter requires developers to upload photos via the upload.twitter.com, rather than the usual api.twitter.com. "Using this alternative host name for the upload path ensures high availability and flexibility," Twitter's Jason Costa wrote in the post.

Unlike some previous releases, such as geotagged tweets, Twitter chose to make photo uploading available first on its own website. Location information was included first in the API before eventually being rolled out to the main site.

Twitter photo upload will also be expanded to the company's mobile apps "soon," according to the post. It's unclear how this will affect current photo providers included in those applications. Twitter for iPhone, for example, has used other services, such as the Twitpic API, to post photos in the past. The app has a handful of image services pre-installed, with the ability to add custom providers. Twitter will no doubt put itself as the default provider for new installations, but it will be interesting to see whether it adjusts the setting on current users, or removes other services entirely.