Which phone should I upgrade to?

[Shay<3]

I currently have the black Samsung Galaxy S2 i777 but I dropped my phone and cracked the screen, so instead of just replacing it i want to upgrade to a newer phone. I'm stuck between the iPhone 4s, iPhone 5, Galaxy S3 and Galaxy S4.

I watched some reviews and comparisons on youtube, but I'm still not sure which to get. I use my phone mostly for web browsing, pictures, texting, and social networking like instagram and facebook. A lot of people were saying an iPhone 5 is not a necessary upgrade if you have the 4s and the same for the Galaxies. Coming from the Galaxy S2 would it be better for me to skip straight to the newest versions of the phones?

I have sprint as a carrier if that makes any difference with the phones.