Lyft and Uber are in constant competition over which can deliver the better ride-hailing service. Beyond that, the companies are also vying to deliver their customers the best promotions.

However, now ... Lyft isn't playing fair. The company announced Monday that it will launch a "Bieber Mode" promotional feature in its app Friday (Nov. 13), giving Lyft riders a big discount on Justin Bieber's new album, "Purpose," which is slated for release on the same day. The promotion is scheduled to run from Nov. 13 through 19.

Sorry, Uber, but nothing spells a win quite like appealing to screaming teenage girls and young women in their early 20s than by utilizing their heartthrob, the Biebs, in a promotion. If the company gets 10 percent of Bieber's 69.4 million followers on Twitter to sign up for the service solely because of this promotion, that would mean close to seven million new customers. Talk about Bieber Fever.

Upping the ante is the 21-year-old pop idol himself appearing in a promotional video for Lyft and surprising riding passengers and fans, teasing that he could be giving you a Lyft on your next ride with the app, too.

Any Lyft customer who selects the "Bieber Mode" feature Friday and spends at least $5 on their ride will be prompted to download the "Purpose" album for another $5 within the Lyft app. That's a significant discount, considering the same LP is $12.99 on iTunes. For what it's worth, riders will also receive a $5 credit to their Lyft account when using Bieber Mode.

The company is about to be Lyfted by a serious dose of Bieber Fever — brilliant marketing.