Yazen
Banned
You'd be amazed but most iOS devices can really only have about one tab open in Safari, and switching tabs forces the previous page to be reloaded.
Instead of the resuming screen (which I cant say I see a lot of), iOS apps flat out stop and you have to wait for the whole app to re load from scratch. I've had this on my 4S, and my iPad. $600 equipment rendered useless. Try copying text from Safari into OneNote. Absolute hell. I've never had to deal with that on Windows Phone thank god. I'll take the resuming screen any day.
What drives me bonkers in WP is OneNote. I love OneNote so much and the app on wp8.1 is so barebones. It is always open instantly though so I cant complain too much. I wish you could pin notebooks to the start screen like the tablet app.
Background Downloading in IE and other download apps. It doesn't exist and it means you have to stay on the download page before the task completes. You also can't open tabs in the background on IE which is stupid.
Tabs are now staying open for me on L1520 WP8.1 (Denim).