T-Mobile is celebrating Cyber Monday by offering a special deal for iPhone fans, selling higher-capacity iPhones at the price of lower-capacity models.

This time of year all sorts of attractive deals pop up all over the place, making many devices more affordable than ever in order to lure in more customers. With Black Friday deals now over, many companies, retailers and carriers are spicing things up for Cyber Monday. T-Mobile is no exception, and the Uncarrier now has a special limited-time offer for iPhone fans.

A few attractive iPhone deals are now available on Cyber Monday from T-Mobile. Today and today only, Dec. 1, the operator is offering special discounts on the iPhone 6, iPhone 5S, and iPhone 5C, allowing customers to upgrade to a higher-capacity model with more internal storage at no additional cost. The deal will not be available in retail stores, as it is an online-only offer.

"Starting at 2:01 am PST on Cyber Monday, buy a new iPhone online at T-Mobile.com and T-Mobile will give you a free memory upgrade. This offer is only available online and inventory is limited," the carrier announced.

Under this new Cyber Monday promotion, interested customers can pay for a 16GB iPhone 6 model, for instance, and get a 64GB model instead, at no additional cost. This will translate to $100 savings off the $750 price tag the smartphone typically sells for. The 64GB iPhone 6 normally costs $749 outright or $99 down followed by monthly installments with T-Mobile.

Similarly, interested buyers can also purchase a 32GB iPhone 5S and receive a 64GB model instead, or buy an 8GB iPhone 5C and get the higher-capacity 32GB model, again at no additional cost. The 32GB iPhone 5S costs $599 and the 8GB iPhone 5C retails for $449, but both devices are also available for $0 down on the carrier's monthly installment options for customers who prefer to get the devices subsidized.

As previously mentioned, these limited-time deals are available online only, and will last until 11:59 pm PST on Dec. 1, or while supplies last. To learn more about this special offer or to take advantage of one of these three attractive Cyber Monday iPhone deals, head over to T-Mobile's website at this link.