While I've known about bluetooth phones for the past few years and heard you could do cool stuff like use it as a modem, control your pc, and sync your computers with your phone, I didn't really give it a try until I got back from Etech this year. In the few months I've been playing with it, I can say one thing's for sure: it's like living in the goddamned future.
What it is
Understanding bluetooth is pretty easy, it's just a name for a low-range networking standard. It's essentially "personal area networking" meaning you can connect a phone to a wireless headset or a mouse with a computer, all without wires. There are a bunch of bluetooth enabled phones and PDAs out now, and thanks to USB adapters, powerbooks and PCs can play too.
My current setup entails a Sony Ericcson t68i phone on t-mobile, paired with a 12" aluminum powerbook. The follow's a run down of how to set it up and what you can do with it once it's in place.
I started by swapping the sim card from my old phone (a samsung I bought specifically to take photos and post online) into my partner's t68i and vice versa. I was surprised that this Just Worked, but it did. Once it was my phone I called t-mobile customer service and dropped my t-zones service for transferring photos and signed up for their unlimited GPRS internet service for $20/month. I asked for setup help, and they forwarded me to a tech that helped me figure out how to setup the account on my phone and what the CID settings were. I got an SMS a few minutes later with all my settings automatically stored onto the phone as well.
I fired up my powerbook, updated bluetooth to the latest firmware, then ran the "Setup a new bluetooth device" option in the bluetooth menu. I left everything on the defaults then when it asked for an access number to get online, I simply entered in *99***(your CID value)# where (your CID value) depends on your phone but is simply a number. That should add a bluetooth modem to your network preferences and I added the icon to my menubar so I could connect whenever I needed to.
And just like that I had a permanent backup connection whenever wifi was not available. No more worrying about which hotels have network connections and how much they cost. No more getting lost while traveling because I forgot to print a map. I just pop open my powerbook, start the bluetooth connection to my phone, and I'm connected.
In the 20-30 hours I've gotten to use my phone as a modem I've enjoyed a connection that seems to run right at the reported 20kbps speed. It's just a tad slower than a 28.8 modem, but is entirely serviceable for email and web browsing. Reading weblogs with lean code and CSS and RSS feeds is easy as well as reading email on the connection. Bluetooth does seem to suck some battery life out of the phone. I went from a full charge to about 50% left after a couple hours of bluetooth'd connection at an airport recently. The time to connect is fast, only taking a few seconds to establish a connection and bluetooth seems to work fine if I leave the phone in my pocket.
There's something impressive about leaving the phone in your pocket and getting a connection just fine (though you do have to fight the urge to yell "Hey everyone! I've got the internet in my pants!"). WiFi is revolutionary but I take it for granted. Playing with data connections over bluetooth, it feels like the first time I tried WiFi. It's almost magic that I can stand almost anywhere in the US, and pull down data from the air, via a wireless local connection to my phone.
While operating heavy machinery
You know how you can talk on your cell phone while driving at a high rate of speed? If you've got a good cell connection, you can transmit data as well. I'll give you a second for that to sink in.
This means while you're (or better yet, someone else is) driving down the freeway at a high rate of speed, you can connect and browse the web and download email from your laptop. I don't know why, but at first I figured this was impossible to do reliably. I've had tons of calls drop off in the last ten years I've used cell phones and voice quality is often less than 100%. If I want to downlaod 50kb of email, at some level I thought every byte is sacred and less than 100% perfect service would result in an unreliable data connection. In practice however, driving across the country at 70mph while downloading email and browsing the web works just fine. It even worked perfectly fine when I tried it on Caltrain, the commuter train line in the Silicon Valley.
Connected via bluetooth on the Caltrain, my laptop near the window as the houses roll by
This recent revelation that you can connect on freeways and trains has really opened up the possibilities. There's little stopping someone from doing a 2004 version of Travels with Samantha, but using a cellphone to post stories and photos from the road along the way.
Bridging the usability gap
One thing about cell phones that's always annoyed me is the keypad interface. You end up spending hours keying in your contacts whenever you get a new one, only to lose them afterwards if you ever switch phones or lose one. Bluetooth on the mac makes this problem a thing of the past by allowing you to link the address book application to your phone via bluetooth. When I switched to this new phone, I simply added a few entries to the Address Book that weren't already there, then sync'd up my phone and I suddenly had 40 phone numbers loaded up. As long as my future phones are bluetooth equipped, I'll never have to key entries in by hand. This is a very cool thing and one of the reasons why all my phones will have bluetooth from now on.
A cool bluetooth/t68i helper app I had to try out was Sailing's Clicker app. It installs a whole bunch of little applescripts that can be fired off from your phone. While it was fun to stand 10 feet from my laptop, point my phone and advance songs in iTunes, change the volume, and give powerpoint and keynote talks using my phone's buttons, I can't see this being totally practical for frequent use. The only actual useful feature I did find was incoming calls could be triggered to pause iTunes and set your iChat status to away. I usually leave my phone on vibrate and unless it's nearby on my desk or in my pocket, sometimes I miss calls. With the visual and audible changes on my mac desktop, I most certainly would know there's a call. The downside of this app is battery life on my phone. Without bluetooth on, I can go 3-4 days before I need a charge, but with Clicker connected via bluetooth all the time the phone's nearly dead in about 24 hours. After a day of playing around, I haven't used it since.
More Gadget Freakdom
Lastly, there are a whole host of bluetooth devices out there that you can connect to your phone, laptop, or both. I've got a Jabra Freespeak wireless headset, and it can connect to my phone and my mac. The sound quality is really good on phone calls and after you get used to tweaking it around your ear and jamming the piece into your ear canal, it's really comfy and you hardly feel it after a few minutes. On the mac, you can use it to iChat people using video or just live audio (using iChat as a phone), and it's ok, though the sound quality is kinda so-so.
I haven't tried out bluetooth mice or keyboards on my powerbook since I hear they don't wake sleeping macs (you can't just shake a bluetooth mouse to wake it up like you can with a usb mouse), and I hear the battery life is an issue (changing batteries once/month or recharging often).
I'm looking forward to the integration with cars. This has been problematic so far, but I think it's only because we're in the early stages of adoption. I can't wait until I have a car that is aware of my phone and can turn down my music when it rings, or transmit data (directions, car status, location, etc) to and from my phone.
It all started when a friend smuggled a phone from Finland into this country 2-3 years ago, and I saw his wireless headset that seemed too Star Trek to be real. Fast forward to today, and my own personal setup isn't just feeling Star Trek, it's actually useful.
So far the killer app is data over the connection. Whenever I'm out of my office and beyond the reach of free wifi, I'm on bluetooth. I hear that pricing for Bluetooth is still all over the map (which can bite you in the ass if you travel a lot) but my t-mobile plan has been a solid $20 in the months I've had it, and it even allowed for free data use when I was in Canada recently (on the rogers network I think). I'm still amazed you can speed across the land while downloading email at the same time, and the little gadgets like headsets are also quite useful. I know Bluetooth has been around for a while and no one ever thought it'd be ready for prime time, but that time is now, and the useful applications of this technology are plentiful and easy to use.
updates: A lot of people have sent in tips but here's one I didn't know about:
"One thing your article didn't mention is the how Mac's Address Book can work with Bluetooth. When you have Address book open you have the little BT button enabled, address book will have a popup with the name (if in the address book) and number of the person calling. This is great when you're at the computer but you're phone is across the room or in your pocket or whatnot. The popup will let you send the call to voicemail if you don't want to take the call." — Kirk