As well as making it possible for a consumer the chance to check out a selection of providers, there is a few other explanations as to why you may wish to SIM unlock your cell phone before your contract ends. For anybody who is going overseas for example, you might want to use a local simcard whilst you're there to stay clear of heavy roaming fees. Or when you've decided to sell your mobile phone then you'll probably get additional money and even more interest in a mobile phone that is free to work with with almost any network carrier.
There's nothing criminal about unlocking your device. It's yours and you are within your rights to use it with any network you desire. Unfortunately, there is a very good chance network unlocking your cellphone could end your warranty, so it may well be best to hold-off until you have finished your contract before you make your mind up to get rid of your existing provider.
When your phone is unlocked, you are ready to locate the least expensive cellular plans on the market - a pay-as-you-go package. A lot of these usually work on a rolling month-to-month basis, that means you can use the offer as long as you are content with your smartphone or you can up date when the next model hits the shelves or your much loved old device eventually fails.
If you're unsure where to go, I highly recommend Unlock.Zone. I have used them personally and was very happy with the service I received, and ultimately that they successfully unlocked my mobile. They offer unlocks for all major manufacturers and carriers, give a guaranteed price match promise, and most significantly, offer a no questions asked refund policy in the unlikely event they cannot unlock your cell phone.
Here's a URL for their site: IMEI Cell Phone Unlocking