Step-by-Step Guide
So here is the step-by-step guide on how to turn your iPod Touch (and iPhone) into a 3.5G iPhone! This is suitable for beginners as it involves no hacking at all of the iPod, and only a simple registry edit on the Windows phone.
What You Need
1) An iPod Touch or an iPhone.
2) A Phone/PDA with Windows Mobile 5 or 6.
I tested this on a HTC Ameo/Athena with WM6 but it should also work on any other touchscreen WM5 or 6. I've read that it will probably not work on the non-touchscreen Pocket PC versions. Your best bet is probably the O2 XDA Mini S which goes on eBay for around £150-200 new or £90-100 used. You can get it free from O2 if you really want a contract. It's otherwise known as the HTC Wizard. Anything from the HTC range of PDA phones should be fine.
3) A SIM card. These can be bought for 99p from almost anywhere now.
4) Download and install the free PHM Registry Editor onto the Windows phone. You can get it from www.phm.lu/Products/PocketPC/RegEdit/
Hey, don't panic! I'm not going to ask you to actually use Wince ;-) At least not once you've done the initial setup. The Windows phone just acts as a mobile access point that can stay hidden in your pocket or bag.
The Procedure
This should only take about 10-15 minutes.
1) Setup the Windows phone as follows:
a) Go to settings/connections/wifi
b) Select the network adaptors tab, and select your Wifi card (should be obviously named)
c) Manualy set an IP address, lets use 192.168.1.1 Then click in netmask and let it auto-fill with 255.255.255.0
d) Go back to the Wireless tab, and select NEW network (make sure the option to show both fixed and adhoc networks is selected).
e) Name the network whatever you want. I called it 'iPod'. Then tick 'This is a device-to-device (adhoc)' option. Hit 'Next'
f) Turn off data encryption. You CAN use it, but it makes things more complex, and only 1 device can connect to this network anyway so nobody else will be able to use it.
g) Hit next and finish. You should see the network name appear with 'Connecting'. It will sit there untill you finish the client side before it says connected.
2) Configure the Internet connection sharing,
a) Run Internet sharing on your device, select 'Bluetooh PAN' and check the box below shows your GPRS data connection.
b) Open PHM Registry Editor and go to 'HKLM\Comm\ConnectionSharing\PrivateInterface=BTPAN1'
c) Change 'PrivateInterface=BTPAN1' to 'TIACXWLN1', Ok and save this. Exit the registry editor.
3) Configure the WiFi settings on your iPod/iPhone (these instructions are for iPod Touch. Presumably iPhone is the same or very similiar. Just let me know in the forum how you get on!)
a) From the home page tap 'Settings' then 'Wifi' then 'Turn on WiFi'.
b) Select your new 'iPod' network from the list. Wait a few seconds. It should connect.
c) Press the 'Home' button and open Safari. Go to a webpage. It should connect with no trouble. I occasionally got the message, 'Cannot connect to iPod'. Turning it off and on (rebooting) should fix this. If not, reboot the Windows phone also and start from scratch.
And that's it! You've ended up with an iPhone that is 3G, is slimmer and lighter, and cost about 10 times less than an actual iPhone! Have fun with this and do feedback in the forum with any suggestions or further ideas.
Limitations and Followup Ideas
Ok, the first thing you might say is 'So how do I make voice calls on it? Well, if you're really sad enough to want to do that, then clearly you can't with an iPod touch because it doesn't have a microphone. I suggest you just take a normal phone out of your pocket and use that instead, as it's much more sensible for voice calls. You could even use the Windows phone in your other pocket if you don't mind looking like a complete dork holding a PDA to your head.
The iPhone could conceivably make VOIP calls this way, over a 3G network. I will let you know if anyone tried this with success!
I have tried MSN Messenger using the great web based messenger service, Meebo. It also allows you to use Aim, Yahoo and Google Talk, although I haven't tested those.