TracFone and Net10 are both providers of cellphone service and prepaid phones in the U.S. These phones are available at many retail stores, including Walmart, and also from the companies' websites. Though their offerings are similar, and many of the phones they offer are identical models, their phones aren't interchangeable. You can't use your Net10 phone with TracFone's service.
Phones are Proprietary
TracFone's and Net10's phones are made for use only with the company that provides it. There's no way to use a Net10 phone with TracFone minutes, nor can you use a TracFone with Net10 minutes. If you have a Net10 phone and service and you want to switch to TracFone, you have to buy a TracFone phone. The good news is that since the hardware is often similar, things like chargers and other accessories that you bought for a TracFone LG500G will work with Net10's LG500G, for example.
Models are Similar
Many of the phones sold as TracFones are the same models as those sold as Net10 phones. Each company has phones made by LG, Motorola and Samsung. They both have a variety of styles, including clamshell phones that are hinged and open to reveal the keypad and screen, candy bar phones that have a keypad and screen on one side and don't fold, slide-out keyboard phones that have a full QWERTY keyboard that slides out of sight when not needed, and touch-screen phones that have one side that's taken up mostly by a large touch screen that serves as the main control pad for the phone.
Pricing Works Differently
TracFone's minutes aren't all the same price. If you buy them in larger increments, they cost less per minute. Each airtime card also comes with a stated number of service days, which also varies depending on the cost. Net10's claim to fame is that all of their minutes cost 10 cents each. However, this is only partly true, as it sometimes has sales on minutes and it also offers automatic payments plans through its website, as does TracFone, that result in lower-priced minutes and even an option for a flat monthly fee.
The term "contract" doesn't really apply to either TracFone or Net10. Both provide service as long as you keep your account current, but you don't have to sign a contract. You can stop paying when your minutes run out and you won't have to pay any kind of early termination fee like you would with AT&T or Verizon. Because of this, you have to pay up front to get a phone instead of getting a phone that's subsidized by the phone carrier.