Personal Hotspot: All you need to know for sharing
One of the most useful features to come with iOS 4.3 is Personal Hotspot which replaces the old tethering option. In addition to USB and Bluetooth connections, Personal Hotspot adds wifi sharing by up to three devices. So you can now feed internet to your iPad, your MacBook and also keep a couple of friends happy—all from the one SIM card in your phone.
Glenn Fleishman of Macworld has published an excellent and very comprehensive ABC of personal hotspotting and I'd recommend it to readers. While he spends time talking about AT&T, users in other countries will soon work out what they have to do. With AT&T you need to authorise tethering and add a data subscription before you can use the service. I suspect this is true of most carriers. Strangely, as I found out, my iPhone contract with Vodafone had no block on the use of tethering or the Personal Hotspot. It worked as soon as I connected. Nevertheless you will still need to add a gigabyte or two to your plan if you intend to connect often to your laptop.
My phone plan includes 1GB of data, included in my £20 per month fee. For a further £10 I've added 1.5GB to bring the total up to 2.5. Previously I had a separate data account with 3GB per month usage costing £15. It appears that the rates here in the UK are considerably cheaper than AT&T's costs in the USA.
There is just one aspect I'm unclear about. Will the Personal Hotspot usage be calculated separately by Vodafone or will I have access to the full 2.5GB to use as I wish between the iPhone and all my devices? I could get get no sense out of customer support at Vodafone (they were unaware of the iOS 4.3 update and insisted on confusing "hotspot" with the 1GB BT OpenZone allocation which is also included in my contract. I've written a letter to head office in Newbury and await a clear explanation which I will relay here.