The smartphone apps for MirrorFootball.co.uk and 3am.co.uk will be available in the New Year, a press release said.
The announcement follows the Guardian's launch of a paid-for iPhone app this week, which was downloaded more than 9,000 times in its first two days at a cost of £2.39.
A price for the apps is yet to be decided, a Trinity Mirror spokesman confirmed to Journalism.co.uk.
This is the latest development for the sites, which were launched as separate properties from Mirror.co.uk in August. Focusing on football and gossip, the sites purposefully ignore search engine optimisation recommendations as part of Trinity's attempts to build a "more engaged audience", associate editor Matt Kelly said at a recent industry conference.
The MirrorFootball and 3am apps will be joined by releases for the Daily Mirror and Daily Record in 2010, which will launch free-to-download applications. All of the planned apps will feature advertising.
This is the latest step in Trinity Mirror's mobile plans: the Daily Mirror launched its mobile website in October last year, following the creation of mobile sites for 13 of its regional titles.
"Brands have demonstrated that it is possible to successfully position themselves in both the mobile internet market and applications market and benefit from both," said Rick Gleave, Trinity Mirror's head of mobile, in the release.
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