Between these 2 phones is pretty obvious the gs3 is better. Facts speak for themselves.
That isn't a fact at all.
To the OP you shouldn't need anyone to tell you why you should choose which phone or platform. My girlfriend and I each got a iPhone 5 on launch day for a few reasons. P.S. both of us had unlocked Galaxy Nexus's prior.
1. Hardware
It seems that the hardware both aesthetically, constructional, and functional wise is heads up above much of the competition. The galaxy nexus radios (wifi and signal wise were weak). The GPS on my phone didn't work at all so having the great native Google Maps was useless to me. This was the second Samsung phone I've owned that had a crap GPS. The first was the Epic 4G. The pentile screen on the Galaxy Nexus was also terrible. Artifacts when watching videos, grainy and lines through the screen. The iPhone screen is true to colors,clear, bright, can actually display white, and has all sub pixels. The wifi chip is superb and the camera is fantastic.
2. Updates, if there is a update you're able to update your phone immediately. On android not so much, unless you purchase a nexus which I did but as stated above had many issues.
3. Ecosystem, iOS has the best apps. The performance of the apps are smoother in comparison to android often times. Also there are many iOS exclusives not available on android. And often times you have to wait forever if a app is to crossover (many don't). Forget people telling you your locked into iTunes. Android doesn't have a official sync app. I have to root to back up app data. And on android you either use the google play store or the amazon app store (many just use the google play store) so its the same thing. My girlfriend works in the medical field as a registered nurse and there are great medical apps on iOS.
4.Customer serivce, no android oem can give you anywhere near the customer service Apple can. If you have a problem no need to deal with the carrier take a trip to a Apple store and get great service and painless replacements if necessary.
5. Battery, the actually battery life is better most of the time. I mean actually usage. In my experience android couldn't compare at all in actual usage time. Thats accross phones and tablets (I have a nexus 7 and iPad 2)
6.Integration, if you have to be integrated into a system iOS is often preferred over android.
7. Stability, android on 4.0 and 4.1 has greatly improved the stability of android. It is a huge difference from previous versions but I still give the lead to iOS.
8. Resale value. If you switch phones often and sell your old phone and put in the difference to get a new one no other phone is going to retain its value better.
There are some shortcoming of course like not being able to change the default apps. The stock apps do work well though. Not having a choice on screen sizes, although not everyone wants a 5inch screen on their phone. Contrary to what some on android central believe. Just weigh what is most important to you and make your decision. I'll keep my nexus 7 to still be in the android mix. I may or may not sell my galaxy nexus.