[AT&T, Rogers, Bell, Telus Samsung Galaxy S III] crash822:
Turn off auto brightness and keep it dimmer. In doors I usually have my brightness at around 25% or 35% and this is more than enough for me. Obviously turn it up if going outside.

Turn off syncs you don't want. I saw that you mentioned that you are on at&t and by default it has pictures to sync with picasa. Turn this off as it'll KILL your data, it'll be uploading your pictures all the time and with cameras getting higher and higher resolutions they make larger and larger files.

Some people say that juice defender is a good app to use to save battery. Personally I never liked apps like it that turn off data/wifi when my phone screen is off because for me it usually takes too long to turn those back on.

Stay away from auto task killers.

No real tests that you need to run.

Can't think of any major settings that are a must to run. I would advise not to use the power saver mode that comes with stock as that thing made my phone a piece of ****.

Can't think of any major streaming music services that are exclusive to android. There is google play that gives you the option to upload your music from your computer to their cloud and then it'll stream your music to any device you want. I'd say download whatever apps you enjoyed on your iphone as many are on android as well. If you can't find an app do a google search for an equivalent on android.

After a factory reset when setting the phone up, it should give the option to have the phone backed up with google. If this is checked whenever you finish the setup it'll start to download the apps you had. I can't remember off the top of my head but I did see a method on XDA front page several weeks ago that gave information on how to back up your apps without rooting, might want to look into that if you don't want to root.

There is no easy way to go from white to blue as they are part of the case of the phone. The only way to change without going to the store for an exchange is to rip your phone apart which I would advise doing. There are plenty of protective cases to choose from though.

Don't know if it is still around but there was a tips and tricks thread for the S3

Things I can think off of the top of my head:

Swiping the side of your hand(think ninja chop) across your screen will take a screen shot.

Disabling s-voice from using the home button double press will make your home button return you to your home screen faster.

Buy a screen protector is the only bit of advise I can give you.

With all that being said, if you really want to increase battery life I'd advise rooting. This'll give you access to cpu control apps. The s3 is the first phone I've seen which has a cpu governor set to default at performance. The cpu governor is what determines how your cpu will scale it's speeds, ie going from 300 mhz to 500 to 1500 etc. The performance governor will only allow two speeds, the lowest speed and the max speed. This makes your phone very snappy but isn't battery efficient. A cpu app like set spu or voltage control will allow you to change your governor to something that is more kind to your battery.

Feel free to look through the forums for other apps you might want or info. If you're feeling really confident I'd advise trying a custom kernel or custom rom as they'll open up a whole new world to you, just make sure you research on how to recover your phone from a softbrick/return it to stock. I'd also like to suggest you make a nandroid backup of your phone before flashing anything in a custom recovery.

One more thing I would give as advice is to try a different launcher like apex/go launcher ex/nova/adw. These give you themes to modify your phone easily and without root.

I forgot one last thing to add. REDDIT!!!!