While Windows Phone 8 GDR3 is right around the corner—and, yes, I'll be writing more about this important update soon—I recently received some information about Windows Phone 8.1 that may be of interest. Due in 2014, Windows Phone 8.1, codenamed "Blue," will address some issues with the current release of the OS and will include some surprising changes, if my source is correct.

Note: While I've independently verified information from this source that is not included in this post, the information you see here is from a single source only. So while I do believe it is correct, you've been warned: I'm not as sure of some of this information as I normally am when I decide to publish. But I felt this was too interesting to not discuss it.

First up, Windows Phone isn't perfect, and while I feel it offers a superior platform and user experience to competing platforms, it's fair to say that sales haven't yet matched potential.

I've been trying to find an accurate customer satisfaction score for Apple's iPhone, but the firm's executives have said recently only that there is a huge gap between their score and that of Android, or that of their rivals generally. (For example, in a recent Bloomberg Businessweek interface, Apple CEO Tim Cook said that "when you look at things like customer satisfaction and usage, you see the gap between Android and iOS being huge."

Well, he's right about that. But customer satisfaction in iOS/iPhone is also much better than that of Windows Phone, which sits at only 53 percent, according to my source. This is higher than that of Android, so Windows Phone is number two. But it's not anywhere close to iOS.

The biggest contributing factor in Windows Phone user dissatisfaction, and in returns, which is apparently quite high, is the lack of apps. I'm told that Microsoft believes it is only 10-12 key apps away from being where they need to be. But you may recall that Microsoft has been trying to fix this issue for almost two years now, and it's not clear how they plan to get there now.  

With regards to Windows Phone 8.1 specifics, there's been a lot of news floating around about possible feature additions, including the long-awaited notification center. But I'd like to focus on a few things I'd not heard about before. These include:

Universal binaries. Microsoft is currently pushing the notion of universal binaries that would let developers create a single app that can run both on Windows RT and Windows Phone. This is opt-in because of size issues, apparently, but could eventually become a requirement. Where Windows Phone 8 has 33 percent "API unity" with Windows RT, Windows Phone 8.1 will hit 77 percent.

Multitasking. Microsoft has supposedly flagged multitasking as Windows Phone's biggest technical issue. GDR3 will fix some issues—it will let users manually close apps, for example—but notifications and background processes are a mess and quite inefficient. These issues will apparently be addressed by 8.1.

Bigger screens. Where GDR3 is widely expected to support 5- to 6-inch screens, 8.1 will supposedly support 7- to 10-inch screens as well. This obviously infringes on Windows RT/8.x tablets, so it's not clear what the thinking is there.

No more Back button. Aping the iPhone navigation model, Microsoft will apparently remove the Back button from the Windows Phone hardware specification with 8.1. The Back button just doesn't make sense, I was told: Users navigate away from an app by pressing the Start button and then open a new app, just like they do on iPhone. And the "back stack" is ill-understood by users: Most don't realize what they're doing when they repeatedly hit the Back button.

Low-cost/volume vs. High-cost/luxury. With the Lumia 520 and 620, Windows Phone has found its niche in the low end of the market. This has helped sales, but Microsoft has always wanted to position Windows Phone as a high-end system like iPhone, which is where the money is. Obviously, they're not going to walk away from market share gains, but low-end phones have technical limitations that harm the platform's forward progress. And this is what sank Windows PC sales when the netbook arrived. The push to 1080p screens and bigger devices will determine whether Windows Phone can break out of this mold.

Again, take this all with a grain of salt. But this information appears credible. And I knew you'd want to know about it.