Pretty much as unlike the US, Oz uses the standard system for mobile phones - but is the the cost of unlocking an iphone going to be less than buying a cheap unlocked phone either somewhere in Europe or in Oz especially if your current supplier doesn't like people doing it.

You could also consider looking at using Skype via a wireless network for contacting home which might remove the need to unlock your phone or buy sims & call time

Could you get 'International Roaming 'if your phone provider offers this? Usually only available on a plan rather than pre paid. Should cost very little for the minimal use you need.

Should work. Always switch off data roaming under Setting and General. Just buy a mini Sim in the first EU country you arrive at and use it throughout Europe. Rates are capped and you retain the same number, handy for others to contact you. Just find out how you can top-up your credit outside the country you've bought it in, or do one big top-up before leaving the country.

"And if so, will charging my phone be a problem? (ie, if i bring a universal power adapter?)."

If you mean a "plug adapter for the different countries" then yes, that's all you'll need as you have 220v in Oz.

If possible you should consider getting a PAYG sim from the 3 network in Italy. Their rates are very competitive and when you travel in Ireland and the UK you can use the 3 network there and have the same tariff as if in Italy paying only a fixed connection charge. In other words no unlimited roaming fees. 3 Italy also offers a cheap data connection charge of 5 euros for a 30 day period which would enable you to make Skype calls when there.

"Could you get 'International Roaming 'if your phone provider offers this? Usually only available on a plan rather than pre paid. Should cost very little for the minimal use you need."

Thats what i would have thought too. But A friend recently went to Europe and relied on roaming. She was careful & phoned her provider b4 she left to discuss rates etc. at worst, she anticipated a few hundred extra. On return to Australia, she was billed $16,000. The cost was incoming calls to her from Oz, charged on her roaming. For that amount legal action ensued & her bill reduced to under $2,000. She was saved by the recorded discussion when she asked about costs as there was no disclosure about charged incoming voice calls.

After her experience I'll never take my SIM out of Australia, regardless of which server I'm with just to be sure.

Unlocking with vodafone seems reasonable. Their website says at most $100, less $25 if done online (looks easy) & less further $50 if the plan is older than 6 mths. Looks like the European SIMs will do the trick. Thanks all. I'll look for the types mentioned.

UK providers don't charge for incoming calls, so that problem won't arise. If you can get your Aussie provider to unlock the phone, a European SIM will work out a lot cheaper, and calls between EU countries are supposed to be capped from July. A prepaid SIM is a good idea, because you top up when you run out of minutes, so always know what you are using.

Yes, you can use your Aussie charger with an adapter plug, and will need one for UK/Ireland, and another for France & Italy. Another solution, albeit more expensive, is to buy a European charger plug from an Apple store.

A charger from a European apple store is a great idea. Are the power sockets (plug prongs) the same for each country? Ie: 1 charger will fit all?

Not sure about Oz but here in the states we can get ones that are semi-universal, with prongs that retract/extend as needed. I have two which are on holiday in Ireland as we speak. At least my belongings are getting to go have fun this summer.

The individual Apple chargers are so small they look almost like ordinary plugs. I have one for the UK which came with my iPhone, and bought another for the US, which can also be used in continental Europe with a Schuko adapter, and in the UK/Ireland with a three-pin adapter.

Check the Apple store in your area to see what is available. Probably the best would be a charger that fits a Schuko (continental) outlet, which could be used with a small adapter plug in the UK and Ireland. The drawback is that they are more expensive than a simple adapter plug. The advantage is they are much smaller than the clunky adapter plugs for Aussie/UK outlets.

After doing a bit of research, I have ordered a gosim for my Australian iphone4. Its prepaid, works all across europe, gives me a mobile number that people can call me on that doesnt charge for incoming (plus folk back home can send me free texts)

If I stay anywhere long enough I can grab a local sim, but between the gosim and wifi I think i'll be covered.

enjoy your trip

It's almost never a good idea to use your home carrier's international roaming. The horrible experience of getting a bill for $16,0000 is bad enough. But do you enjoy being charged $1 or more a minute per call.

I wouldn't get one of those international SIM deals anymore either. Convenient, yes, and I have used on in the past. But at today's European cell rates those international SIMs are charging you double, triple and more.

Look at Lebara.fr and lebara.co.uk. You can even order SIMs before you leave if you are creative with the online order form... you'll pay pennies a minute.

As for unlocking... if your phone company won't do it for you there are places near where I live who charge $50 to unlock a 4S. I'm sure there are where you live too.

You can't use your iPhone 4s with other carrier if it is locked to a network.First,you have to unlock the carrier lock to use it with other network.You can unlock it using Remote Unlock Service provided by online vendors.It is very easy and safe than other unlocking methods.Visit http://www.simpleunlocking.com/apple-iphone-4s/rs16wp9/ to get Remote Unlock Service by providing country and current network name.You can use your iPhone 4s with any GSM SIM card after it is unlocked.I don't have any idea about the charger issue.But,when you are there if your charger doesn't work then you can buy a charger from any European apple store.

newmario: Welcome to Fodors. Perhaps you didn't notice the thread is from last June? I'm sure the OP's trip is over and done with.

Out of curiousity I checked the link provided by newmario above. More like 'ripoff mario'. I plugged in my country and provider and was quoted a price of over $180. I can have the job done while I wait locally for 50 bucks. Ignore mario's advice.

I have used travelsim in my iphone 4s. Not perfect but it really kept the costs in check.