If the Lumia 920 was launching against the iPhone 24 months from now, I'd consider switching but right now, I'm moving back to iPhone after a rather sour experience with Android.
The Lumia is a technological marvel. Windows Phone 8 is beautiful. That's the good.
Now, the bad. Windows Phone has no apps. Microsoft can't get their act together and the WP7/8 debacle is just more evidence of that.
So, while WP gets its act together and builds a strong base (if that's possible), I will continue to go with other solutions. iOS does what I want. My past iPhones almost never crashed. I don't need to tweak my phone to the end of the earth; I was a sysadmin for a multi-domain corporation as a day job. I did all the "tweaking" I needed to do there and at home, I just want my shit to work. Apple provides a good solution to that and after dealing with an Android phone that crashes the UI at least three times a week (fuck you, HTC Sense), I'm more than ready to move back to a device that doesn't make me want to throw it in a river.
In short, I don't give a damn about specs. I want a phone that runs smoothly, has a multitude of apps, and doesn't fuck up several times a week. The iPhone 5 will do all of that and more.
And who wants a 5" screen on their phone? Having the option to buy one is nice but after using the One X I told my dad to buy a month ago, that screen is just too damned big. I don't want anything larger than 4.3" on my phone so a 4" screen on the iPhone 5 is just fine by me. I already own a tablet, I don't need a miniature version that makes phone calls.
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