T-Mobile US Inc. (NYSE:TMUS) has been one of the biggest stories to come out of the 2014 International Consumer Electronics Show this year in Las Vegas. With the announcement of its Uncarrier 4.0 plan, which will pay a customer fees for leaving their current mobile carrier for T-Mobile, T-Mobile hopes to cause a major disruption in the mobile phone industry.

Not only will T-Mobile help alleviate the cost of switching, it is also helping customers, who may feel an emotional connection to AT&T Inc. (NYSE:T), Verizon Communications Inc. (NYSE:VZ) or Sprint Corp. (NYSE: S), end the relationship by composing a “break-up letter.”

T-Mobile Break-up Letter T-Mobile's marketing strategy for its new Uncarrier plan allows users to send a "break-up letter" to their old carrier. Photo: Facebook

Using a Facebook app, T-Mobile lets users choose from a list of common complaints of mobile carriers, sign their name and send it to their ex-carriers. Users can even download the letter and print it, if they feel so inclined.

Of course it's nothing more than a marketing ploy, but it is representative of T-Mobile’s ability to be fun, think outside of the box and effectively use social media to promote its brand.

T-Mobile knows that it can’t compete with larger mobile companies when it comes to advertising budgets, so it's getting creative with social media and publicity stunts. On Monday, T-Mobile CEO John Legere went uninvited to a CES after-party hosted by AT&T, and used news of him getting kicked out to generate anti-AT&T sentiment on Twitter.

If you switch to T-Mobile, will you write your old carrier a break-up letter? Let us know in the comments section.