I can give a few reasons for my shift from Android to iOS. Many people here have mentioned quite a few reasons which hold for me too: less buggy (qualitative), iOS is very good at regular stuff but android might be very good at geeky stuff (yeah, I consider some customization to be geeky), faster updates, quality of hardware, quality of 3rd party apps, etc. Of course you can argue otherwise and there is no way to do a 1-1 comparison in full fairness, because each comes with their own good and bad.

However, I have an example which describes my feelings on iOS mathematically. The android experience feels like points on a N-dimension space. Lets compare it with 2D, each dimension being the quality of a feature e.g. (2, 10) means 2/10 on feature 1 and 10/10 on feature 2. Due to the presence of so many HW and SW variants (due to different update cycles), the available pairs of numbers are huge. Also, being a 2D number there is no comparison between (2,10) and (10,2) since normally you can't compare objectively between two features. Note that this is a property of the N-D numbers too :). However, iOS features seem to be lying on a single line (with a few exceptions, mostly due to SE). You always get all the features right-away and if you decide on what features you want, you can easily decide on what to buy.

In my opinion, the Android market is slowly moving close to what the PC market is. Lots of options, but hard to say which is the best. Many qualitative opinions, but when you get down to the details, some brand is very good in one feature but lacking in another. At least, in my opinion, in iOS/Apple space, if one of the products is lacking a feature, the whole market is lacking that feature - so at least the decision is easy. There is nothing that makes you question your decision :)

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