What do they mean by Prepaid carriers?

Prepaid, means you pay a specific amount, and can use the phone services as long as you have a balance in your account. It is not charged monthly, only when you phisically decide to add money to the balance.

nsnarayan10 wrote:

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off-contract iphone 5 for $599,does that mean the other sim can be inserted without unlocking the phone?...

No. off contract just means you aren't tied paying a monthly fee for a specified ammount of time usually 1 or 2 years. Its the same as calling it Prepaid. The Phones are still locked to the carrier.

nsnarayan10 wrote:

And they also have some cool monthly plans,so does this look better than contract phones?

Monthly plans are contract based.

nsnarayan10 wrote:

Ok,this Virgin Mobile USA iphone 5 is still carrier locked but only advantage is that we dont have to pay monthly bills like we do on Contract phones,right?

Correct,

nsnarayan10 wrote:

And is contract phone cheaper than off contract phone?Look I can afford full price of device and I dont have to switch sims,but I would like to know if contract phone is cheaper by the time the contract concludes?

Thank you so much!

That mostly depends on the type of plan you get. While it may be cheaper upfront, in the long run it may not be.

Think about it this way, off contract: you pay $599 upfront, and that's it.

Monthly, you'll pay say $299 for the phone, but then you'll pay monthly $59 for a middle of the pack plan for 24 months. That's about $1400 + $299 for the phone. Obviously you pay more with the more costly plans.

If you don't use a lot of data (stick to Wifi), and make very few calls, and very few text messages, you may be better off with the Off contract phone.