I had an iphone 4 for 2 years. so i've passed through from ios4 to ios6. To be honest, i was getting tired of the damn phone, it was starting to have frequent bugs (it would freeze, apps would crash, sometimes when i opened a text message from the lockscreen the damn phone would just turn off, etc...) but i liked it. It served me well and it was a reliable phone for 95% of the time that i've had it. I never jailbreaked it because i like to keep my things in oem state just in case everything FUBAR.
I would have kept it an other year if the damn screen had not broke because of a 2' drop (and also because my carrier did not want to renew my contract so **** them. for any canadian, **** telus.)
So 6months ago, i went out and bought a Galaxy S3. I absolutely love it. it does have some major flaws (shit battery life, but it aint worse than the iphone's by the end of its life) but the amount of things i can do with it is just amazing. i just wish that i had more than 2gb of data/month. Other than some minor teething issues, it just roflstomps the iphone (whatever model you have.)
TL;DR - if you want a nice and reliable phone out of the box, get an iphone.
if you want something better, go get something else that runs on android or windows.