If you find that your cell phone is locked it is not the end of the world and there is a way to unlock it so you can use the phone as you wish. A very simple and straight forward way to unlock your phone is to call your network provider associated with the phone. Try samsung unlocking for your Samsung cell phone. In most cases you can simply tell the provider that you would like to unlock the phone. When you do this they will usually be able to unlock the phone immediately, or within a few hours time. This will allow you to place any SIM card in your phone and use it, which gives you the versatility that you are looking for.
If your network provider does not want to provide you with the unlocking, you can still use the phone you just have to take matters into your own hands. You can find Samsung unlock codes on your own. There are a lot of different services that you can find via the internet that will provide you with all of the unlock codes that you could need for any phone that you want to use. You simply enter in the code and your phone is unlocked. At this point you should be able to place any SIM card in the phone.
If you are going to be traveling internationally it is important to have an unlocked cell phone. The reason for this is that you may have to replace the SIM card that is already in your phone with one that is from that country for it to work properly while you are there. If your phone is not unlocked it will not allow for you to use it when you are in another country.
Having an unlocked phone will allow you to use your phones as you wish. If you want to use one phone instead of another you should be able to, because it is not the phone that belongs to the network or that allows for you to use a network, it is the SIM card within it that stores all of the information, so the SIM card should be able to be put in any phone that you want, so long as the phones that you are using are unlocked!