The You Choose service, which rolls out gradually this month, works in the same way as Orange's Shots service, by sending ads to opted-in customers via SMS and MMS.
The service enables customers to send return messages back to the advertiser for free.
Herbal Essence, Pot Noodle and Empire are among the first brands to send out content to T-Mobile customers using the service.
Orange Shots was launched in February 2010 and in April this year, the network provider extended its relationship with the mobile messaging media company Blyk to power the service.
In May, Everything Everywhere signalled its intent to expand its ad sales offering, and appointed its first director of mobile media and advertising.
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