I can't agree with the above comment. Samsung went down to their 'pathetic' build quality race post 2010, before that period all devices were made really good, device like Wave was of brilliant build quality. It started with S3, carried on to Note 2, S4, Note 3, all are horrible. Now they have learnt their lesson, and S5 seems to be of far better built.
Secondly what's wrong with their ASS? I bricked my S2, which was rooted, so officially they were restricted to receive the device, but they did and un-bricked it. I have personally not had any problem with them, nor I've heard anyone having any problem!
Samsung devices do NOT lag, it's Android what lags! iOS is a completely different ecosystem, as well as WP, so there's no point in comparing them IMHO!
As I said, regardless of the bugs, infamous force close and some other freezing / rebooting issues, Android does have a lot more advantages over any OS, there's nothing you can't do with it. Now whether you need it or not is up to you. But you never know when you're gonna need something.
WP : Plain & simple. Not bad. App quantity and quality is nowhere near of Android, not yet. Lack of customisation, hmm. Well it's still an efficient OS, at least it won't let you install another ****ing app in your PC, so you won't be a dog.
iOS : I better not comment. Cause it gives me a pain to even write anything about it. The only advantage it has that app quality, they are indeed better, not in functionality, but overall responsiveness, less bugs. But a person, who is like me, needs less than 50 apps, it doesn't make a bloody difference. A sodding OS can't play a Matroska file out of the box, when I used it I couldn't even set an MP3 as ringtone, that beautifully accurate map, I'll die before installing that iTunes crap on my PC again, I don't wanna go on.....
Build quality is crap, just like S4. The difference is plastic vs cheap glass, both will shatter!
As I said, my parents will have no problem. Cause all they do are clicking on that Dialer icon, type in some bloody number and call that person. Then check a message or two. And if really pushed check something on internet. When I asked my mom after buying a L520 for a mere 7k for her that what difference do you see between this and your previous phone, she says the previous one was slightly faster, but this one is good too, I like it. That previous phone happened to be an iPhone 4, a sodding device I bought for 32k, from a friend of mine, who bought it for 39k and sold to me after using for three months. I asked him why are you selling this, he said that phone was too good for him, didn't get the sarcastic part that day, but I get it more than anything now.
I'm sorry and no offence to anyone but I really have no interest to lose some precious IQ to use an iPhone.
PS : Forgive if any grammatical or spelling mistakes were done, it was Swyped.