In truth you really only have 3 main options with international cell phones, and the major factor that will affect your decision is whether you want the easiest and most convenient option, or the option that has the cheapest call rates, because you can only have one or the other.

1. Check if you can use your own cell phone

If you have the right type of cell phone, you may be able to use it when you travel abroad. If you are unsure then your carrier should be able to tell you. The advantage of taking your own cell phone is that you will keep your own number so it will be easy for friends to call you. However, using your own cell phone can be more expensive due to roaming charges (the extra charge added for routing the call abroad).

Conclusion — potentially this offers the greatest convenience but be prepared that your calls will cost you more. The most likely outcome will be that your carrier does not offer an international service, or if they do, you do not own the right type of handset.

2. Rent an international cell phone

If you cannot use your own cell phone abroad then you can rent an international cell phone that will work, just for the period of your trip. The cost of the calls will vary, depending on what type of SIM card the rental phone uses. If it uses a global SIM card then your calls will be higher priced, but if you are traveling to a number of countries you will keep the same number. If it uses a local SIM card your calls will be cheaper, but you will need a different local SIM card for each country you plan to visit.

Conclusion — rental sounds like a good idea, but you can now buy your own second cell phone, just for traveling, for the same price as one or two weeks' rental charges, so that might be a more cost efficient option for you.

3. Buy your own international cell phone

The cost to buy your own second cell phone, just for international travel, has now come within the reach of all travelers. As with renting an international cell phone, the cost of your calls will depend on what type of SIM card your phone uses. If you use a global SIM card, you will keep the same number in every country but your call charges will be a little higher. If you use local SIM cards you will get cheaper calls but have to buy a different one for each country you visit in the future — this can start to get expensive if you are a frequent traveler.

Conclusion — If you cannot use your own cell phone, buying a second one is generally more cost effective than renting every time. If you want a system that is easy to use then a global SIM card will be the best for you. If you bottom line is cheaper calls, and you are happy to put in a bit of effort to get them, then buy and phone and use local SIM cards (but don't overlook the cost to buy each individual SIM card when you do your price analysis).