T-Mobile (NASDAQ: TMUS) and Sprint (NYSE: S) know that people buy gadgets, including smartphones, on Black Friday, so both companies have gotten into the mix with deals to kick off the holiday shopping season.

Like all deals from wireless companies, both offers are a little bit confusing because of all the conditions involved. That's not an attempt to deceive anyone by either company -- it's simply a fact of doing business in a world where prices and incentives change based on whether a person has a device to trade in and the age/model of that phone.

Here's what Sprint has for Black Friday

Sprint is promoting its offer to cut customer's bills by 50% if they switch from one of the other Big Four carriers. But that's not a Black Friday-specific deal -- it's been running for quite a while.

Its actual big Black Friday promotion is already available: A buy one, get one free deal on the Samsung Galaxy S7 with no special conditions. If customers don't want a second phone, they can opt for a free Galaxy Tab E instead with an S7 or an S7 Edge.

Customers can get also a new HTC Bolt on Thanksgiving or Black Friday for 50% off. The carrier also has a number of other deals which are being offered at least through Cyber Monday, which it touts in a press release.

What T-Mobile is doing for Black Friday?

T-Mobile's deals also involve the Galaxy line. The company is offering a free Galaxy S7 for any customer who trades in an eligible phone. In addition, those users will get a free Gear VR and a $50 credit for virtual-reality content.

The No. 3 wireless carrier is also offering a free tablet -- either a Galaxy Tab E or an LG G Pad X 8.0 to anyone who signs up for a qualifying data plan. And, like Sprint, T-Mobile will be making a number of accessories, and other devices available at sale prices through Cyber Monday at least in its stores and on its website.

Is this the time to buy?

Getting a free phone or two-for-the-price-of-one deal can dramatically cut your cell costs. These are solid deals -- maybe not better than those offered randomly throughout the year, but good enough for anyone looking to upgrade or add a tablet to their plan without breaking the bank.

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Daniel Kline has no position in any stocks mentioned.

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