iOS 4.3 brings a nice little feature with it called Personal Hotspot. When enabled, this feature allows you to connect up to three other devices to your iPhone's cellular Internet connection via Wi-Fi, Bluetooth, or USB. I have it enabled on my AT&T iPhone 4 and will give you an overview of how it works.
First I want to point out that this is not the first time you have been able to share your iPhone's Internet connection. There have been several ways to do this in the past as long as your iPhone was jailbroken. iOS 4.3 marks the first time that you can "officially" share your Internet connection on a GSM iPhone in a way approved by Apple. The Verizon CDMA iPhone has had this feature since it launched a few months ago, so even though it isn't yet eligible for the 4.3 upgrade (Verizon iPhones are up to iOS 4.2.6 as of this writing) the feature is already there.
Once the feature is available on your iPhone you will see it listed under the Settings > General > Network menu. The feature is carrier enabled, meaning that each wireless carrier can determine whether or not you can turn it on, and also if they want to charge you extra in order to use the feature. In AT&T's case they have decided to require a 4GB per month plan at $45 per month in order for the Personal Hotspot feature to be available. The price itself is not bad, as the standard 2GB plan is $25 per month plus $10 for each extra GB used. So essentially you are just paying for 4GB of data and are not being charged an extra fee on top of the regular data rate. Personally I'm not a fan of this model because you have a limit on your data plan to begin with. If I decide to share my Internet connection and I exceed the 2GB that I already pay for then AT&T is still going to charge me for the excess data, so I don't see why I should have to guarantee that I'll spend $45 for the 4GB of data just to get the Personal Hotspot feature to be enabled. Obviously this is just a moneymaker for AT&T.
Strangely AT&T specifically prohibits using the $45 per month plan for "corporate email, company intranet sites and/or other business solutions/applications". I'm not sure how they can tell if you are using your connection for those purposes, but that's the official rule. For business purposes they offer an enterprise plan. The enterprise plan is exactly the same, offering 4GB of data, yet costs an additional $15 per month for a total data plan cost of $60. Again, another obvious moneymaker for AT&T.
Just in case you haven't guessed by now, the Personal Hotspot feature is not compatible with any grandfathered unlimited data plans from AT&T (although that would have been nice). If you want to enable the Personal Hotspot feature you will have to give up your unlimited data plan for good.
The first time you try to enable the Personal Hotspot you will receive a message informing you that the feature needs to be added to your account first. Once you add the feature to your account (which can be done easily through the AT&T website) you will be able to access the Personal Hotspot menu. By default the Personal Hotspot is turned off. The iPhone will also randomly generate a WPA2 password to protect your network (in my case the random password was "leaker3326" which seemed a little odd). You can easily change this to whatever password you want.
Sliding the Personal Hotspot switch to the "on" position enables the feature. By default the Personal Hotspot will be enabled for whichever radios you have enabled in your iPhone. If you have both Wi-Fi and Bluetooth turned on then they will both be available for Internet sharing along with the option to use a USB cable directly to your computer. If either Wi-Fi or Bluetooth are disabled when you turn on the Personal Hotspot feature you will be asked if you want to enable them.
One thing that immediately caught my attention is that you can not change the SSID name of the wireless network that your iPhone creates. It is set to be the name of your phone, so in my case my iPhone began broadcasting a wireless network named "Josh Duglin's iPhone". I don't know about you, but if I'm at the airport, in a coffee shop, or any other public place where I would most likely use the Personal Hotspot feature I certainly don't want my name and the fact that I have an iPhone network shared being broadcast to anybody with a laptop or smartphone.
Once you have enabled the Personal Hotspot feature for the first time it will then appear as an option on the main iPhone settings menu so in the future you don't have to go very deep into the menus to turn it on and off.
When you have the Personal Hotspot turned on it will be seen by your other Wi-Fi devices just as any other wireless network would be. Simply select the name of the network from your other device, provide the password that you chose, and you will be connected to the Internet through your iPhone's cellular connection. Once another device has connected to your iPhone you will see a blue bar along the top of the screen indicating how many other devices have active Personal Hotspot connections to your iPhone.
I tested the Personal Hotspot feature by connecting both an iPad and a laptop computer to my iPhone 4's internet connection. Both were able to use the Internet at acceptable speeds. I averaged just under 3Mbps down and just over 1Mbps up when using the Personal Hotspot. Not too shabby at all. Interestingly the iPad somehow knew that it was connected to the Personal Hotspot and not a regular Wi-Fi network as the network indicator icon changed from the usual Wi-Fi arced lines symbol to the Personal Hotspot icon which depicts two linked chain links. I'm not sure if this changed the behavior of the iPad, but I did not notice any difference other than the expected speed decrease when switching from broadband-based Wi-Fi to cellular-based Wi-Fi.
The Personal Hotspot feature on the iPhone is a welcome addition and works quite well. If you need to occasionally use other devices (such as an iPad or laptop computer) away from a regular Wi-Fi network then this feature is by far the easiest and cheapest way to go. You don't have to buy any new hardware and even though I'm not a fan of the $20 per month premium that AT&T charges to enable the feature it is still less than paying for a separate data plan on another device. If you use your other devices away from Wi-Fi networks the majority of the time then this may not be the best solution for you, mainly because of the battery life of the iPhone. Whenever you are using the Personal Hotspot feature you are running down the battery on your other device, as well as the battery on the iPhone. This can be problematic if you use the feature for several hours a day as you may end up with a dead laptop and a dead iPhone. If you have a separate connection for your other device then at least you will still have your iPhone to communicate with once your other device's battery has run out. The biggest complaint I have about the Personal Hotspot feature is the lack of a way to change the wireless network's name. To me this is a major security and privacy concern.
SUMMARY: IPHONE PERSONAL HOTSPOT
- Easy to use when needed
- No need to carry another device for providing an Internet connection
- Allows you to share your total data plan allotment as a pool across multiple devices instead of having a separate data limit for each device
- Carriers can require additional monthly costs in order to enable the Personal Hotspot feature
- While using the Personal Hotspot feature you are running down your iPhone's battery in addition to your other device's battery
- No way to change the name of the wireless network that the iPhone creates
- Enterprise use requires a $15 premium for the same amount of data
VERDICT: This is a great feature to have available if needed. Even though you have to pay more in order to use it you are still just paying the regular data plan rates. So if you are already using 4GB of data on your iPhone then adding then Personal Hotspot feature is essentially free. As I've mentioned in previous articles, this is a great alternative to the 3G iPad as you can save money on your initial purchase and also save money on your monthly bill while enjoying the benefits of having your data limits pooled together. Unfortunately the fixed wireless network name kills the whole deal for me. If Apple releases an update to allow the network name to be changed then I will be able to recommend this feature. As it is now though I cannot recommend the Personal Hotspot feature due to the security and privacy concerns that the fixed network name brings with it.
BOTTOM LINE: NOT RECOMMENDED (for now...)