All you need to know about the Windows Phone 8.1 'Preview for Developers'

Last week, Microsoft announced Windows Phone 8.1 to the world. We gave you numerous video tours of the OS, and we’re sure you watched Joe Belfiore's on stage demonstration of Cortana. Microsoft also announced that the Preview for Developers Program will go live for 8.1 "sometime in April". That program will allow you to install the 8.1 update early on any Windows Phone 8 device. Every. Single. One.

What is this program? How can you prepare for it before it arrives? Head past the break for all you need to know!

What exactly is the 'Preview for Developers' Program?

Back in June 2012, Microsoft revealed plans for the ‘enthusiast program’ for Windows Phone fans.  It was during the Windows Phone 8.0 announcement and many people here on this site were tantalized by the prospect of getting updates earlier and faster than carriers.

That’s what the Program is for. It’s labeled ‘Preview for Developers’ but in reality, it’s for anyone with a Windows Phone 8 device, as the barriers to participate are extremely low (more on that below). Microsoft is well aware that carriers tend to drag their feet on updates, so this is their way around that roadblock. It’s a sly move as Microsoft actually wants you to use this Program.

Unfortunately, details were sparse at the time of the announcement in 2012. Sparse as in there was just one line in a PowerPoint presentation that mentioned it. Fast forward 18 months later and Microsoft finally got the Program setup, just in time for Windows Phone 8 Update 3 (and before fans nearly revolted).

Will it run on my...

Yes! Lumia 520, Lumia 525, Lumia 620, Lumia 1520, HTC 8X, Samsung ATIV whatever...you can 'Preview' 8.1 on all of these phones and get all the same features, even Cortana. Cortana is only available in the US? Change your region or just use the default Bing search like now.

Is this a hack or will it damage my phone?

No, this is not a hack. It’s still an over-the-air update that is pushed by Microsoft. Technically speaking, things could go wrong, just like with any OS update. In reality, we have had zero complaints or problems reported to us with the previous Preview for Developers. Literally zero. Even Microsoft confirms the same, with almost 185,000 people participating in the program. So yes, it’s safe.

But be advised, there is no “rolling back” the OS. Then again, we’re not sure why you would want to.

Will it erase your phone?

Nope. It’s an over-the-air update that will only update/refresh the OS. Your apps, games, contacts, photos and even settings should remain the same. This will not wipe your phone.

Will it void your warranty?

It depends. It’s actually up to your carrier or the manufacturer who made your phone. To be honest, we don’t have much to go on here because we have had no reports come in to serve as a test case. As far as we know, no one’s phone has been damaged enough to warrant this action. Even still, you do have the Microsoft support forums should any problems arise. Likewise, Nokia is pretty darn good for service.

Keep in mind, once the “official” update goes out, your phone will look the same as someone who just waited for the update, meaning it will be impossible to tell it from any off-the-shelf phone with 8.1 installed. All phones are equal, post official update. That leads us to…

What’s the difference between this and the official update?

There are technically two parts when it comes to official updates:

  1. An OS update aka Windows Phone 8.1 build xxxx.xxxx
  2. A firmware update specific for your phone and carrier (if sold through one)

The OS update is universal; it works across all devices and, for all intents and purposes the Preview for Developers is the same OS update as the official release. This is not a beta version of the OS.

The one difference is the Preview for Developers does not include new firmware.

All the firmware does is enable some device-specific functions, most notably new camera improvements on Nokia devices or the new SensorCore APIs, which will come with the Lumia Cyan update. With the OS update though, you’ll still get 100% of the all the 8.1 features announced, you’ll just keep your current firmware.

What happens when 8.1 officially rolls out for your phone and carrier?

Basically, nothing. Nothing in the good sense. Your phone will get the same update, but unless the OS is different, the only thing that will be updated is your firmware. After the update, you’ll be on the same page as everyone else.

In other words, you risk not a thing by doing this.

How do you signup?

If you’re already a Windows Phone developer, then you don’t need to do anything except download the app (see below). If you’re just a regular person without an ounce of coding skill, then you can sign up for Microsoft’s App Studio: appstudio.windowsphone.com

Cost? $0

Just sign in with your Microsoft ID and let them register your email address. That’s it.

Next, you need the Preview for Developers App for your phone, and you probably need to have Update 3 already installed, though we’re sure most of you already do.

Get the Preview for Developers App

Now that you are a registered ‘developer’ with Microsoft, you need to download the app to your phone. This app, published by Microsoft, lets your phone register with Microsoft so that they can send you the OS bits.

Run the app, sign in with the same Microsoft ID you registered with App Studio and check the box that says ‘Enable Preview for Developers’. Likewise, you can always uncheck that box and unregister that device.

Watch the above embedded video to see it all in action!

When will you get Windows Phone 8.1 Preview for Developers?

Microsoft has not announced a specific date, just a timeframe of April. All we can say: pay attention to our site as we’ll be the first to tell you when it is live.

Once it’s live, you head into your device Settings > Phone Update > Check for updates. The OS update will begin downloading immediately, and the program will walk you through the process (note: it’s the same process as every other Windows Phone over-the-air update).

You’ll want to have a battery with at least 50% charge and have access to Wi-Fi, as OS updates can be large – too large for some carriers. Also, you should have at least 1 GB of storage space available, as that update has to be downloaded and unpacked somewhere!

When will you get the official 8.1 update with new firmware?

It will be contingent on your carrier and phone manufacturer. Since this will be like previous updates, you can expect a rolling schedule spanning a few weeks to even months as each carrier has their own time frame. From past experience, we’d push this out as far as July and August for some of you, with the Lumia 810 on T-Mobile probably not getting it at all (blame T-Mobile).

Anyway, hope this quick guide helps. Prepare now so you’ll be ready whenever Microsoft throws the switch!

Want to learn what’s in Windows Phone 8.1? Check out our features page or head into our 8.1 forums where you can discuss what’s new!

Daniel Rubino
Editor-in-chief

Daniel Rubino is the Editor-in-chief of Windows Central. He is also the head reviewer, podcast co-host, and analyst. He has been covering Microsoft since 2007, when this site was called WMExperts (and later Windows Phone Central). His interests include Windows, laptops, next-gen computing, and watches. He has been reviewing laptops since 2015 and is particularly fond of 2-in-1 convertibles, ARM processors, new form factors, and thin-and-light PCs. Before all this tech stuff, he worked on a Ph.D. in linguistics, watched people sleep (for medical purposes!), and ran the projectors at movie theaters because it was fun.