Under T-Mobile’s deal, new or existing customers who trade in a fully-paid off recent smartphone can get a free iPhone 7 with 32 gigabytes of storage. Customers have to stay with T-Mobile for two years on its new unlimited plan, called T-Mobile One, or a Simple Choice plan to get full credit for the free phone.

Alternatively, the free with trade-in deal, which T-Mobile offered when the iPhone 7 first came out in September, can be used to get a free Samsung Galaxy S7 or LG V20.

Wireless carriers are upping the ante on deals and promotions as the holiday shopping season gets going. The aim is to attract more customers in a market that is no longer expanding like it did a few years ago. Only T-Mobile and Sprint added regular monthly phone customers recently, while Verizon and AT&T saw net losses in that most lucrative subscriber category.

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Sprint has said it will offer Black Friday customers who buy a Galaxy S7 phone a second S7 phone for free. Or a Galaxy S7 buyer can get a free Samsung Tab E tablet. The HTC Bolt phone will be half off and customers who buy an LG V20 will get a free 43-inch LG 4K UHD Smart LED TV.

T-Mobile (TMUS) is also discounting accessories like wireless speakers and phone power recharging packs. New customers who are switching from a competitor will get an additional $200 per line on a prepaid Mastercard. However, T-Mobile won’t extend to Black Friday its deal that lets customers sign up for 4 unlimited lines for the price of 2, which expires on Tuesday night.

For more, read: Here Are the Best Black Friday Deals for Tech; Here Are the Best Cyber Monday Deals for Tech</em></p> <p>Verizon is offering Black Friday discounts on Google’s new Pixel phone, as it is the only carrier selling the phone directly under an exclusive deal. Customers can get $200 off the Pixel, which sells for $650, or pay $10 a month for 24 months. Verizon will also sell the new Google Home smart device for $100, down from $130.

AT&T’s deals, which started on Tuesday, include a free iPhone 7, Galaxy S7, LG G5 or LG V20 only for customers of the company’s DirecTV or U-Verse services who switch a line in from a competitor. The carrier is also offering an assortment of discounts on other hardware, such as a $200 Visa gift card with purchase of a Samsung Galaxy S6 phone or an LG G Pad X 10.1 tablet for 99 cents with purchase of a flagship LG phone and a two year contract.

When the iPhone 7 was first released, all four carriers offered a free with trade-in offers. T-Mobile and Sprint (S) said the offers greatly increased demand compared to sales of last year’s iPhone 6s. AT&T (T) and Verizon (VZ) said their deals only modestly affected demand.

Analysts think the promotions may have helped sell more iPhones than expected, but Apple (AAPL) won’t reveal actual iPhone sales until January, when it reports results for the final quarter of the year. Even then, the company never discloses how many iPhones were sold just in the United States.