iOS 5's snazzy new notification center offers a great way to keep tabs on your phone's various beeps and buzzes, but iOS 5 also packs a couple of interesting under-the-hood notification features you may not have known about: custom vibration notifications and LED alerts.
Wired's Gadget Lab runs through a handful of "hidden" features that didn't make the marquee during Apple's iOS 5 launch, like its awesome new text expansion feature, system-wide word definitions (highlight a word and tap Define), private browsing in Safari (buried inconveniently in Settings > Safari > Private Browsing), app-by-app usage reports (Settings > General > Usage), and so on. If you'd like to customise your notifications a touch more, then you might want to take a look at the custom vibration and LED flash options.
Create Contact-Specific Custom Vibrations
If your phone spends most of the day in your pocket, on vibrate, contact-specific vibration patterns allow you to identify who's calling without taking the phone out of your pocket.
To create and enable a contact-specific vibration, just fire up your Phone app, select a contact, tap Edit > vibration > Create New Vibration. Tap out your custom cadence (I started with the always-original "Shave and a haircut"), then tap Stop when you're done. You can test your rhythm by replaying the pattern, then save and name it. Piece of cake.
If you feel like you've created a vibratory masterpiece, you can set it as your phone's default vibration in Settings > Sounds > Vibration. (Note that you can also record new patterns here as well.)
Enable LED Notifications
A lot of phones allow you to flash an LED for a more visual alert. To enable LED notifications in iOS 5, you've got to dig down into the Accessibility menu in Settings > General > Accessibility, then enable LED Flash for Alerts. There's a pretty big catch to this one, though: It only works when your phone is in silent mode (that is, vibration turned off in Settings > Sounds and the vibrate/silence hardware switch toggled on.
You should also keep in mind that it's not a persistent flash; as far as I can tell, it emanates one showy series of flashes and then goes away.