Apple’s iCloud is possibly the best thing to happen to smartphones since the touch-screen. Not only does it seamlessly synchronize your data between all of your iOS devices, it does the same thing for your Mac or PC – and – it acts as a tether-free way to backup the contents of your iPhone.

When I recently switched from my iOS 5 equipped iPhone 4 to the loaner iPhone 4S I started using last week, I used the iCloud restore feature to port all of my settings and apps. The result was astounding. After the restore, which by the way was completely done over Wi-Fi – no tethering to a computer or iTunes – my 4S looked like a complete clone of my 4, right down to the wallpaper for my lock and home screens. The only thing I had to do was re-enter my Wi-Fi passwords.

But I digress…

One thing I noticed about this process was, while the backup and restore via iCloud was impressive, my backup size was really big. In fact, I had already come close to using up all of the free 5GB that Apple allots to all iOS 5 Apple IDs. If I only had the one device, that might not be the end of the world. But the iPhone is just one of three iOS devices I use under my Apple ID and there’s simply no way I was going to be able to back the other two up without needing some more room.

But it turns out there’s a simple way to drastically reduce the size of your iPhone backup.

When you go into your iCloud settings, and check out the options for Backup and Storage, you’ll see that each and every app on your device can be set to have its data backed up, or not. Including the Camera Roll. That’s key, because if you’re like most iPhone users and you make regular use of the awesome camera on these phones, you probably have plenty of photos and videos.

When I checked mine, it was sitting at 4.4 GB!

No wonder I was almost out of room. So I turned it off.

Huh? Yep, I turned it off and saved myself nearly all of the storage space I had been sucking up. I know what you’re thinking, but my photos are *still* backed up.

Here’s why: The PhotoStream feature on iOS 5, when turned on, automatically keeps a copy of the last 1,000 photos you’ve taken, regardless of which device you used, on a 30-day rolling period. And those photos do NOT count toward your Backup and Storage capacity. It’s free storage from Apple, and it’s even better than using your iCloud storage space. PhotoStream sends your photos to your computer which is ultimately where you want them anyway.

There’s only one caveat. If you take a lot of video on your iPhone or iPod Touch, you’ll need to remember to back these up manually, since PhotoStream doesn’t backup your videos – only your photos.

One last thought if you’re thinking that backing up your Camera Roll is something you want to keep doing: your iCloud storage space isn’t the only area that is impacted.

When your phone is locked and plugged into power and connected to Wi-Fi, it will automatically backup your data. For most people, that means overnight while you’re sleeping at home.

Consider that even a backup of 2GB can consume a good chunk of your bandwidth cap, it’s well worth keeping your backups as small as possible.

Make sure you check the full list of apps that are backing up to iCloud – most use virtually no room, but some can be hefty. Check out those Songify and Kindle items in the image above. Only 70Mb between them, but I have very few books or songs in there. It could go much higher.