Unlocking your phone so that you can save money on phone calls while travelling
In some cases when you purchase a phone through the network provider they may not be locked, but it's much easier to organise these being unlocked or to check if there locked before you leave. When a phone is locked cannot use it with any other phone provider, that means if your overseas you would not be able to use a local phone company.
The benefit of unlocking your phone is that it gives you the flexibility to choose what phone provider to use so that you can save substantial amounts of money on your phone costs while travelling. In some cases there is no costs to unlock your phone but some providers to charge.
There are two ways to find out if your phone is locked, the easiest is simply to call your phone carrier and ask them they can tell you right away if your phone is locked to the network. Alternatively you can insert a Sim from a different phone provider and see if it shows an error. Locked phones will display an error if you insert a Sim from a different network carrier.
Most people find it much easier to check these things before travelling overseas so that if there is a problem it can be easily solved without having to contact your phone company overseas.