Tom cited lack of apps (not just apps, but quality apps) as his primary reason for switching and also the attention Microsoft was giving to other platforms than its own. You can read his article HERE.
Ed Bott also recently ditched Windows Phone after Verizon failed to upgrade the Lumia Icon (930) to the latest Windows 8.1 update (aka Lumia Cyan).
While many criticized their decisions to quit the platform, surprisingly a lot of WinPhans agreed with their reasoning and I am one of them. See, I've been using a Nexus 5 now for the past couple of weeks and I too got frustrated with Windows Phone. I will definitely switch back (whenever the Lumia Denim update is rolled out). See I have an unlocked Lumia 930 which I had to pay a lot for ($500+), this is due to the fact that Microsoft decided to make this an exclusive on Verizon and the irony is Verizon treated this phone like crap, limited adverts and no-support including no updates since Cyan update released a few months now.
But let's talk about why a majority of Windows Phone users are ditching the platform, Tom Warren and myself included:
1. Microsoft #1 problem with its Windows Phone platform is lack of apps, and where these apps are available, they are either third party apps or sub par to their android/IOS versions.Tom mentioned a few apps he missed, I personally have no problem with the app situation with the WP platform, it is sooo much better than it used to be only a year ago, my main issue is the quality of these apps or lack of an official app and the list is endless... FlipBoard, Instagram, Twitter, SnapChat, Skype, OneNote, Youtube and more.
2. My second reason for leaving windows phone is inevitably noticed, and that's te attention Microsoft is giving to the other platforms. For instance, OneNote for WP does not support password-enabled notes but its IOS version does. Skype for WP does support voice mail but its Android and IOS versions do. Microsoft also released a touch-friendly version of Office for iPad while Windows users are left in the dark. Recently even MSN suite of apps was released on Android (the only google app on WP is a mediocre google search app). It's mind boggling how Microsoft can sh*t on our faces with no blatant regard to our loyalty.
3. This year Microsoft released a ton of low budget WPs, and no upgrade for At&t Lumia 900 or 1020 users, and yea Lumia 1520 is no upgrade to any using the 920 or 1020. A lack of flagship and the persistent rumor that we will not get a flagship till mid 2015 left a sour taste in our mouths and they lost a lot of WP users there.
4. Windows 10 for phones: The last hope, much is being expected of the upcoming Windows 10 for phones that will be unveiled next month. BUt haven't we heard that story before? remember when WP 7.5 (Mango) was unveiled with 500+ new feature/improvements, then there was WP8 that came out a year later that made all WP7.5 devices obsolete and Microsoft is yet again about to release another major update with the same storyline... A lot of WP users have had it with the constant reiterations of the OS and have since left the platform. But hey, maybe a third time is the charm?
In conclusion, for Windows Phone to gain traction they have to do one thing: Make it super easy for developers to port their Android/IOS apps to the WP platform, because let's face it, devs aren't going to waste their time re-coding re-complying apps for a lesser platform. Microsoft fixed the issue with bringing OEMs but making it possible to run WP on hardware that can also run Android now they just have to push it to the apps' side.
They have to release new phones (not low end) in a timely fashion and also release firmwares updates shortly after announcing them.
After fixing the 2 issues above, the last piece of the puzzle is... being innovative. thank God Microsoft got the great innovative minds from Nokia when they acquired their mobile division, so hopefully this wouldn't be a problem.
But Tom makes a good case, one that Microsoft should address soon.