Joe Belfiore just wrapped up his Reddit AMA, here are the highlights

"As you folks know, MS' mobile strategy had a big reset back in 2009 when we changed our model for WP7. At the time, the iPhone had shipped with a new approach to mobile-- touch enabled, big screen, and new functionality.To react to this we had to implement a new system -- a new UI, a whole bunch of apps we hadn't built ourselves (interestingly: the old "Windows Mobile" that MSFT shipped didn't even have a dialer-- it had to be built separately by each OEM!)... And there was a LOT of work to get the same set of features built.So... I'd say we've acknowledged plenty of times over the past few years that we've had features missing relative to iOS or Android. Some of this was intentional decisions to be focused-- we did NOT focus on Enterprise/Corporate at first-- but then we did.I'd say with WP8.1 the feature gap is ALMOST completely closed. As mobile is much more mature now, it's less likely that ANY platform will have ALL the features of its competition -- and that's what makes one platform fit certain people better." (Source)

"We sure as heck try not to break promises. The thing that's tricky is WHAT YOU PROMISE.. And it's amazing how much the internet gives things a "life".Last summer we said we'd enable developers to get updates separately from the carrier-approval process. It took us longer than we would have liked to roll -- this out... but the reason for that was a combination of work we had to do to implement the program AND the fact that the updates we were shipping early in the year wouldn't have had as much value for existing phones.We knew we had BIGGER updates coming later-- the Update 3 last year not only had some solid features in it for everyone (rotation lock, driving mode, storage sense updates) but also carried Update 2 with it. BY THEN it really mattered to get it out. Plus we knew 8.1 was coming, so we wanted the system up and running.In this case I'd say it took us longer, but I wouldn't say it was a "broken promise" (though I can see how people felt that way for some months)." (Source)

"Microsoft DOES NOT treat WP as a second class citizen! We have a very senior, well-funded team that has amazing support from our senior leadership and from other groups.What does happen time to time is that teams who are working on cross platform work make prioritization decisions (or are limited by the nature of WP itself) such that features show up on other platforms first -- we are a company about devices AND SERVICES and when you think about something like Skype it's important that they remain compelling and competitive on other platforms as well.As a general rule, we work with teams to make sure WP users aren't lacking in benefits... and all the teams here are getting better and better at this... Skype now has WP-specific benefits, the Remote Desktop client is out, etc." (Source)

"There's no silver bullet here... Apps, like most things in software development, are a marathon, not a sprint. And I'm not claiming we've nailed it - as you point out, there is more work to do. Fundamentally, the ISVs who write these apps are making business decisions about how they can make the most money-- and as WP has grown, and as MS has invested time & money in the apps, and as the platform has gotten better/stronger... more and more apps have shown up.So -- sitting in 3rd place, it's tougher for us to get the apps-- but I do think that we've made great progress in the last couple of years. We're not resting on our laurels. We (and not just we.. I) are visiting ISVs, looking for ideas that can help them grow their volume and user engagement, providing them with funding and development help - and in some cases we are even using our own team/devs to write apps ourselves.You're seeing these results through both well-known apps SHOWING UP (Instagram last year) as well as higher average user ratings per app on the store - we look at ALL sides of the issue. Right now we're MOSTLY focused on continuing to GET the key apps-- although lately with more of these present, we've shifted a bit towards improving the current ones.You mentioned Skype and FB -- on Skype, we have new version in development that our team (and me) have been using and it certainly helps with performance-- we'll keep going-- and on Facebook, we've been working with FB on an update to that app too, targeted for the June timeframe - this update brings improvements to performance, having full-width photos in the newsfeed, and seeing photos & comments at the same time." (Source)

"Right now, it's not ONE FEATURE. It's the way the whole system is designed and what it's about. We think WP is the MOST PERSONAL SMARTPHONE– and that’s a combo of features, starting with live tiles and now Cortana makes it even more personal. This is kind of a mantra for the team-- we're serious about this. We're balancing a unique, attractive visual appearance with letting the user customize it a ton. We really want your phone to feel like your "fingerprint" ... better than any other phone." (Source)

"Nothing specific to announce, but Cortana herself is always telling us she's a fan of PCs herself." (Source)

"You can turn Wi-Fi on/off by speaking in the developer preview now, but cool suggestion to do this automatically based on location." (Source)

"This was a close call for us –- this kind of situation happens a lot in design... I call it a "45/55 thing". In this case, we made the change (to the "55" :) because we found through usability testing quite clearly that NEW USERS to our platform sometimes had a hard time finding games.. so we chose to optimize for these new users. It’s reasonable to suggest having an option for this in the future... something we’ll explore." (Source)

"Star Wars. Sorry fribbley." (Source)

"We think we’ve developed an awesome platform with Windows Phone, and definitely look forward to welcoming Google’s apps on it. We have these apps high on our "want list" so it's something we've invested in (ahem, YouTube) and are absolutely willing to continue investing in.Unfortunately, the apps are Google's and I can't say when they will act. Only our friends in Mountain View know timing.You should ping them! (Often!)" (Source)

"The time-lag thing is tricky. It depends on: - what LEAKS. (We can't prevent these, and they make people start looking for stuff that may be a ways off). - When we ANNOUNCE. We have to balance early announcements (better for ISVs to get apps ready on the new platform) against waiting to announce close to availability (more fun for end users because you hear about something and then, poof, it's ready to go. Also -- done right, this can help sales because people will hear excitement and then head to a store and find a phone ready to buy.)We are trying to strike this balance in a better way -- with WP8.1, the announce was aimed at devs and just days later we had the developer preview in everyone’s hands, so the MOST motivated users (and there are a LOT of you!) can get the software quickly.We expect to keep our pace of updates similar to what we did last year-- we are pretty proud that we shipped three software updates last year, and we're already working on some cool stuff that I know you'll like.On HARDWARE -- it's trickier. Up until now (welcome Nokia!) it was different companies doing this work, and they had to sync their schedules with ours. We do think that for first party phones, the acquisition will help with time to market... and you've seen us already announce new phones at the same time as announcing the software. I can't comment on any new phones that might be coming-- but of course Nokia and other partners have a bunch of stuff in progress.Last -- we're doing plenty to help HW partners get devices to market faster in general. At build, we showed some phone prototypes for India and China that partners took only a few months to get running.Overall, we feel like we have made some progress in getting to a higher velocity, but we know we have more we can do, and I think you will see us continue to accelerate where we can." (Source)

"Yep, talking/" (Source)

"Music is a good topic for this AMA... lots of interest!There's a balancing act we're trying to effectively walk here... (1) We have a super-valuable audience of subscribers who've been with us since Zune, and who value subscription, etc... And at the same time (2) we're selling the significant volume of phones to people who are NOT Xbox Music (Zune) subscribers and (based on needing to pay a monthly fee) aren't likely to become subscribers. They use music "simply".SO ... we're trying to build an experience that runs cross device on your PC, your Xbox, your Phone-- in a service-oriented way (think: cloud collection)... but simultaneously work for the hordes of people who manually sync content using the shell or iTunes. Getting both of these right has been challenging.We moved away from the PC Zune client in the interest of serving the broadest phone-buying audience in the way they already knew. We learned that many people who ALREADY USED iTunes or the shell viewed learning a new Zune client as a "speed bump" in the way of getting going on a new phone. So, we changed the structure to appeal better to those people.The new experience in WP8.1 Dev Preview will get us to one system that works GREAT for "ordinary side loaders" (it works with the Windows Shell) AND for people who use multiple devices and are more "cloud-oriented". It’s re-architected to handle both of these well-- and in particular we're shipping it as an app on the phone and have committed to regular updates which will make a BIG difference over the next few months. You've seen one already and more are on the way.Upcoming in the app: you'll see performance improvements (we hear you!), better stability, UI improvements (some of you have been asking for a "swipe" to change tracks), etc. etc. Do take a "months" time view of this, as there's plenty of stuff in the pipeline." (Source)

"We'll do more ourselves-- but while WE are always working on various apps, I would also encourage you to work with the /r/windowsphone subreddit because I know there are devs on here who are looking for ideas of what apps to build.We love seeing the community add-value here too!" (Source)

"Developer preview is NOT final... There’s client-side software fixes we're still making, when UPDATES go out to existing phones they will come with "BSP" (low-level phone firmware) updates from the OEMs... and the Services (Cortana) are continually getting improved. SO... when you get an official update or buy a new phone, it'll be more polished than what you folks have now.In terms of timing... no specific dates to mention, and keep in mind that the software updates will vary by phone and carrier. Do keep in mind our history last year with updates to get a sense of how we think about this.In terms of the specific issues you hit -- the dev preview has gone very well from our POV, with hundreds of thousands of "devs" having downloaded it so far (smile), and we’ve been closely monitoring feedback on the platform, features like Cortana, action center, etc.And since you mentioned this, it's a good opportunity to mention our UserVoice site –windowsphone.uservoice.com. The team uses this site A TON to help structure and prioritize feedback on what customers want to see in the product. Yes, I read it myself and I FREQUENTLY send links to people on the team when I need help winning an argument. One of my favorite stories from a previous release about how we use UserVoice was how you can now configure the button in the browser address bar to do what you want – e.g. favorites or tabs. Everyone who voted on that feature, THANK YOU for making your voice heard." (Source)

"Well, speaking for what I PERSONALLY would most like us to implement... a small phone that will fit in my small pockets... But that has HUGE screen size.Maybe like this... http://gifsoup.com/view/3168675/laia-hologram.html" (Source)

"Cortana in other countries: We’re definitely working to bring Cortana to other countries. She tells us she’d like to travel. We've already announced that when we launch V1 after Beta, we'll be in China and the UK as well as the US. We're also hoping to get other English-speaking countries (e.g. Canada, Australia) out relatively quickly as well. The challenge in doing this is we want the Cortana experience to be EXCELLENT for everyone -– and this involves not ONLY delivering great voice recognition for all the different languages, but also making sure that we have a great regional experience with local content so she doesn’t feel like an American!In the meantime, we're thrilled that people are trying it out in other countries and we use that data to train the system. It's helpful to get accents and hear other queries, and we can detect WHERE these are coming from to help improve the experience later." (Source)

"Yeah, I agree this could be better -- it's something we intend to address in the future. For now, we’ve tried to organize it by the most frequently used setting. But we realize that's tricky because people are SO DIFFERENT in what they care most about. Action Center's configurable buttons helps with that-- and btw, we hear many of you asking for extra buttons (e.g. cell on/off) in Action Center and I'm optimistic we'll be able to oblige... but no promises here." (Source)

"Although we do always put you in the ‘web’ pivot when you do a search, you can swipe over to see results from your phone – even when you are offline." (Source)

"Hadn’t heard this issue below… as a tip, you can also hit the back button to close the action center." (Source)

"Good feedback... We’re always thinking about new ways to make our apps more discoverable and generally add the things people are asking for most." (Source)

"YES! We are doing a File Manager for WP8.1! I know a LOT of you are looking for this (thanks for the tweets, I've read them all). In fact, I've been running a build of it on two of my phones for the last week or so and it's getting to pretty good shape." (Source)

"Hmm... Easter eggs... Related to an AMA... maybe you should ask Cortana if SHE'D ever do an AMA." (Source)

"Let's talk Radio first... FM Radio wasn't in the initial launch of 8.0 because it wasn't finished when we made the base-level OS change to the Windows NT core... so it came in the first update. From your POV as a WP7.5 user, it "disappeared" (yes) and then came back. From our POV, we swapped out the kernel and didn't finish this part of the work for a few months. This aspect is one of the tougher parts about software development, we sometimes have to make tradeoffs in terms of features and time as a result of technical change that has benefits that are WAY less visible to users.Let’s take the social integration in 8.1 as another good example of tradeoffs that some of you don't see without an explanation. When we had Facebook and other SNs deeply integrated into the OS code, it was very challenging (and we got a LOT of feedback from customers about this) on two counts (1) because we were missing a number of desired features –- like being able to "Like" a photo and (2) because it limited our ability to do great international support for the key social networks around the world. As you've seen on other questions here, when we end up doing something that doesn’t work worldwide, that causes users pain too. There’s an old phrase that’s been used at Microsoft for a long time about how creating big software projects is like ordering pizza for a million people.. and there’s a lot of truth to that.So after a few releases of getting feedback that people LOVE the UX being integrated but are frustrated by the limitations… we decided to go with the app-powered model for social integration in 8.1. This approach empowers the individual services as well as individual devs. Now new social networks can be added at ANY TIME via an app update, and thus a lot of people around the world will get a feature they've missed entirely. Furthermore, by linking to the app, we have a mechanism for "deep users" to get access to "deeper features" in a nice, natural way.I’m not saying we got it perfect out of the gate – but there are real advantages to the app-powered model in the long run. Besides what I mentioned above, it will get better over time as the apps get updated. For example I mentioned in another reply that we’re working with Facebook on an update to the fb app that improves performance, and that’s in turn going to make the social integration experience better. We’re working with others developers on this too.I would encourage ALL developers to look at this integration as an opportunity – and work with us together to make it better. Give us feedback, write integrated apps, use integrated apps, give developers feedback, etc. etc. etc. Let’s make it happen together.On PHOTO HUB ... we changed the design because we got actual telemetry data on what people ACTUALLY CLICKED. By far, the most clicks when people opened Photo Hub were to go to the camera roll -- and only .5% of clicks were to a 3rd party app. The re-design in WP8.1 addresses this, putting the FREQUENT task right up front and making the other tasks generally available but in a different place." (Source)

"We spend a TON of time with people from other divisions.I have regular 1-1 meetings with my counterparts in Office, Skype, and Xbox. Our teams have a standing process at every milestone for jointly reviewing our work, and we use each other’s products deeply.The environment at Microsoft has been great for us to get better and better at this... And although we sure have room to improve, it's a place that I think has become a strength." (Source)

"Carrier Exclusive phones...in the US and Canada, the carriers value having exclusive phones because they are reasonably looking for any angle to get people to sign up for a long term contract. They are really selling contracts, and their method is to attract with a phone that they promote aggressively. As part of this model, they expect to and DO spend a LOT of money on marketing. When their business works this way, it's very hard for a hw maker to NOT participate because you'd be competing against the money that the carriers themselves would spend on marketing and against the work they'd do to sell other phones against yours in their stores.We understand this creates a dilemma for end-users... you want to buy a phone but it's not on the carrier you're already signed up with. Well, that's precisely the effect the carriers are trying to create, they want you to switch. :)In the higher-volume ecosystems, you have seen this dynamic change... iPhones and Samsung phones are typically the same device across carriers. I expect as WP usage grows and along with that as broader end-user demand begins to ALREADY EXIST in the market, the need for carriers to spend money educating people will diminish and the phones are likely to be more broadly available.SO... in the meantime... try expansys.com or zones.com to buy unlocked phones." (Source)

"The MAIN thing that will affect this perception is whether the apps you use have implemented "Fast Resume". This was a new thing in WP8 (I think -- can't remember if that was the release we added it in) and an ISV has to "flag" their app to support it. This might involve testing and in a few apps it involves more work than just testing. SO ... ping the ISVs if you're feeling that apps come up slow. MOST PEOPLE don't say this.A lot of people ask about TRANSITIONS and they assume the transitions "add time" to getting to the app. We've worked hard to make that NOT THE CASE. What we've done is made the transitions happen "while the app is loading" so they give you something to see that fills the time but does NOT slow it down. (OK, maybe a tiny, imperceptible bit.) We would NOT NOT NOT gratuitously make millions of people wait longer to show a turnstile... we show you the turnstile while you'd be waiting anyway." (Source)

"Multitasking. This is the classic "balance-striking" design challenge. What we've tried to do here is (1) make sure that REGULAR USERS (think: less sophisticated, don't tweak their phones that much) get GREAT AND PREDICTABLE BATTERY LIFE while (2) Apps can do powerful things for everyone (and especially for power users).The biggest killer of battery life is typically an app that's got some kind of runaway process. Usually this would be a bug if it happens-- and it could happen in any app. Thus to accomplish (1), you restrict apps to "runaway" and try to do as much on their behalf as you can.Now, with that as background, know that we've GREATLY EXPANDED the multitasking features in apps with every release, and we'll continue to do that. As app developers are doing more stuff and as we learn about the gaps in our system, we try to enhance. I can appreciate you folks-- generally power users-- hitting the limits of this approach and asking for more... and we hear you.On your TOMBSTONING question-- honestly I can't answer that myself, but I'll pass it on. When we switched the activation model, we chose to make the APP decide so the APP could be sure to effectively manage its own activation. Our intent is that users get apps with "instant resume", but this is a case where we have to trust the ISV to get things right-- kind of like the general topic above." (Source)

"It comes down to this: we want to provide a COMPLETE EXPERIENCE for Cortana, and we want that complete experience to be PREDICTABLY present and not vary too much. If you hear about something she does, we want it to be true on YOUR PHONE, in YOUR COUNTRY.Cortana builds rich inferences by rationalizing across lots of different signals and content that you give her permission to access. For instance, by having access to your location, within a few days Cortana figures out where you live and where you work and starts giving you commute inferences based on when you leave to go to work or come home from work. Without location a bunch of the important end-to-end scenarios wouldn't work or key questions couldn't be answered-- e.g. what’s the traffic like to home/work, remind me when I get at a location to do something, show me great Caribbean restaurants in Seattle, etc.Our current view is that without location Cortana would "feel limited" and we don’t want to create a fragmented experience where some things will work and some things won’t depending on whether you give us access to location. Part of this is that she's entirely new and we want her to develop a GREAT reputation, compared favorably to the competition. Over time, we might make her more flexible so that we can accomplish BREADTH... but right now the focus is on consistent quality." (Source)

"Luckily, I've grown more laid back as I've matured…"