Twitter's mobile ad footprint is about to get bigger. In a blog post  today, the company said that it is expanding its ad presence on mobile apps for the iPhone and Android phones.
Twitter's Promoted Products have already been appearing on the mobile Web (at m.twitter.com) and in limited ways on smartphone apps. But, with its latest app update, Promoted Accounts will be visible in mobile apps and, in the coming weeks, Promoted Tweets will start appearing in users' timelines on mobile apps, the company said.
"Initially, a small number of users may see Promoted Tweets near the top of their timelines from brands they already follow," the company said in its blog post. "This will help ensure that people see important Tweets from the brands they care about." With other advertising products, including the self-service product  which began testing in December, Twitter has taken a similar approach of starting small and improving as it expands.
As with the experience on Twitter.com, the company said, Promoted Tweets in mobile apps will appear with regular Tweets in users' timelines (and like regular Tweets, they will fall off the timeline as users scroll through). In search, they will appear only when they are relevant. Promoted Accounts will be displayed in users' lists of "who to follow" recommendations.
The latest mobile updates don't include ads for iPads and tablets, but Twitter has said that it will advertise wherever people can access Twitter—and 55 percent of its monthly active users access Twitter through a mobile device. So, it's likely only a matter of time before they make their way to tablets, too.