I get the impression there are quite a few iPhone users on here. After resisting enthusiastic friends have persuaded me to try one. It is a whole new world to me, so any enlightenment from experienced owners would be appreciated.
A brief look through Google seems to suggest I can download software free to jailbreak/unlock. Is this reliable what are the advantages/problems? Phone is currently on O2
Thanks! (Apologies if this has been done already)

If you don't know what you're doing or why you're doing it, either keep on reading or steer well clear.

I wouldn't bother with it unless there is something you specifically want that you can only get from jailbreak software.

Give it a try as it is for a few month then consider jailbreaking later.

(Also the latest iPhone OS update from Apple messes with jailbreak phone by prevent them rolling back to earlier updates).

as above unless you really need to do this don't. Apple have been playign around to try and 'brick' jailbroken phones when they release os updates.

If you don't know what you're doing or why you're doing it, either keep on reading or steer well clear.

This^^^ to be honest. Forums across the interwebs are full of people who have jumped in before knowing exactly what they are doing.

Not me tho, happily jailbroke for the last 9 months and all up to date on the OS front.

But as Graham says, just use the phone for a bit it might do everything you need as it is.

Thanks for the good advice – suspect it will do plenty as it is. What about unlocking? I see O2 will do this for £15, which does not seem too bad.

Unlocking is free from O2 if you are on a Pay Monthly contract.
Or £15 on Pay As You Go.

I've just jailbreaked(jailbroke) a 3G that was a gift from my brother in Australia. The phone was locked to Telstra hence the need to unlock it to use on O2 here.
If you use Blackra1n (google it) it's the simplest job ever:
[*]Download a little app from here
Plug your phone into PC
Run app and click on the only button you're presented with ("Make it ra1n")
The app reboots your phone does some stuff in the background and job's done – takes about 1 minute.
[/*]

If you want to unlock the phone you then install "Sn0w" (you're presented with this option when you run the Blackra1n app that gets installed on your phone) which even easier and doesn't involve a PC, all gets done on the phone.
Blackra1n is completely reversible and pretty good. BUT – why would you want to do it? Yes it allows you to use lots of other apps that Apple hasn't approved and you can unlock the phone for use on other networks, but if you have an O2 phone they'll do that for you cheap anyway so I can't see the point really.

On the other hand if you have a non-O2 phone and want to unlock it then Blackra1n/Sn0w is very much your friend 🙂

My son did his, piece of piss apparently, he has downloaded Tomtom for free, it works great, he is going to the States in the summer & he is planning to download the US maps for free.
I too have an iphone but never bothered with jailbreaking.

Tomtom for free sounds good as someone told me it cost around £70 for the i-phone, which seems steep now that Nokia are give sat-nav away free for life. Where from?

TomTom on the iPhone isn't as good as CoPilot Live or Navigon, going by reviews I've read. Navigon needs another 59p app to get full 7 digit postcodes, but CoPilot is only £25 for the UK. I'm not sure that Nokia maps give full turn by turn voice navigation. Tip: if you're downloading big apps with maps in, download via iTunes then sync the phone and they'll copy across, but they do take some time. Having installed CoPilot and Outdoor South West England I know how long it takes, and how much space they take up. (Lots). I honestly can't think of any reason to jailbreak; there are so many apps available for free or are really cheap that I can't imagine any point. The ebook apps are free, and there are loads of free books available through them. The main reason I'll pay even for quite expensive apps is I then get continual free upgrades for the life of the app, and that applies to the Ordnance Survey apps like Outdoor too. Then there's the ongoing phone OS upgrades on a regular basis as well, iOS4, the next big one, is rumoured to bring multitasking in, and that should be in March, with luck. Why go through all the hastle of keep swapping back and forth to get the upgrades?

Thanks CountZ – that is very helpful and appreciated advice.

WHat ze Count said +1

I just don't see the point in jailbreaking – unless you really know what you're doing like GrahamS type geeks 😛