iphone or samsung galaxy s3

I have looked at many sites comparing the 2 phones, they all seem to contradict each other...
Apple has the most following, samsung seems in some ways to be the better phone..
It has a bigger screen , that will help me...but its a plastic case..
then what plan...telstra has $80 a month on either business plan..unlimitd calls during the day.it helps me as I use it for work..
that includes the phone cost..