Useful tips for developers to avoid Windows Phone app certification failures

Whether you are an individual, hobbyist Windows Phone developer or part of a developer studio that builds Windows Phone apps, it’s quite an effort to develop, test, and market the apps.

Therefore, it hurts when an app submission fails certification, and you have to correct and resubmit the apps. Not only does it increase the effort and resources, it also delays the app release and any marketing plans.

In a post on the Windows Phone Developer Blog, the Windows Phone Store certification and policy team shares the most common certification failures they see as apps go through the certification process.

App Screenshots

The most common reason for certification failure is not adhering to the app screenshots requirement. Your app screenshots should not include any emulator chrome, frame rate counters, or debug information. They should not be altered or be transparent. Also, photos of your app running on a device or the emulator are not substitutes for a screenshot taken with the emulator.

It’s not too hard, really. Use the built-in emulator screenshot tool and don’t take WVGA (480 x 800) screenshots for Windows Phone 8 XAPs. Instead, use the Dev Center feature that automatically scales the XVGA screenshots down to the WVGA resolution.

Also, while the screenshots are not required to be localized, you do need to provide at least one screenshot for each language supported.

App Testability

If your app require a login, make sure you create a test account that can be used by the certification team during testing. Don’t forget to include the account credentials in the Certification notes in your Dev Center submission.

App Closure

This one is a no brainer! Certification will reject your app if it ‘unexpectedly terminates’ during testing. BugSense and Little Watson can help you collect unhandled exception telemetry data.

Required app images

Developers sometimes forget to replace default icons and tile images in an app created from a Visual Studio template. Other tools such as App Studio and Apache Cordova also provide default images that are to be replaced with unique icons and tiles that reflect your app. The default images are useful placeholders to let you know the required size for these assets.

Use of Back button

The Back button behavior is narrowly defined, and with a few exceptions it should close the app, go to previous page, close an open dialog, or close the soft keyboard.

Language validation

For each of the languages your app supports, you must provide a localized app description. You can use the emulator to quickly switch between phone languages. Certification testing also verifies that your app displays properly for each of the languages your app supports.

Content and themes

The app submission requires that app displays properly in both light and dark themes. In Visual Studio the Device Window allows you to toggle between the dark and light themes giving you feedback on the visibility of your UI items during layout.

By avoiding these common certification failures, you can build apps that pass certification faster and with fewer rejections, and hit the Store on schedule. Also, don’t forget to check out the comprehensive list of Windows Phone App Submission requirements (opens in new tab).

Abhishek Baxi
  • I personally think certification should be tougher, for more quality apps. Sure, that would probably empty 25% of the store, but there are honestly lots of crapps (see what I did there). Microsoft touts all these apps, with their certification and what not, but some of them, bugs aside, are nonfunctional or uneccesary. Again, all in my opinion, but I think it would make for a more fluid and richer store experience.
  • One man's trash is another man's treasure. If no one wants the trash it sinks to the bottom of the ocean
  • Second that, because historically MSFT have a tough certification procedures, also we maybe in third place for the marketplace 140k vs 1millon on apple and 600k on android but our market must be in a good percent clean of trashy programs.
  • How so only 600k on Android?
  • As a developer I too sigh when I see my app below some apps that I feel should not be certified. The trouble is that if they use a subjective vs objective decision making process then you risk issues where an app may be technically sound but the person reviewing may just not like it. I have had some people say they think my app lacks appeal etc. because it is not one you would "naturally" search for when looking for apps for your phone. But I went on to make it and it has been featured on the Nokia blog etc. Imagine if that one person who said it wasn't "necessary" was the one approving my app? I think they however could be stricter on things we can all agree on, technical specs.
  • Actually crappy apps will always exist no matter how tough a certification procedure is. The problem is really how the store present these apps. So far the WP store is a mess when it comes to sorting and featuring apps. The noteworthy section has tons of apps that are only rated with a single star. Microsoft need to work on the store, refine the filtering methods they use, maybe take queues from Apple as IMHO their app store is the best experience there is in smartphones currently, its well organized and grouped. MSFT needs to add top lists, users and staff picks, and feature more than a single app a day.
  • Good tips all around especially the testability one. Forgot to include login information and had my app fail the first time. Also for windows 8 its important that your app works with keyboard/mouse. Some things that work with touch may not work on a touch less system esp using the mouse wheel to scroll.
  • i have a few idea but never developed before and i heard its time consuming. i dont have a surface but the RT, will i be able to create apps on my tablet or would  need pro or a desktop?
  • You have to have full Windows 8 64-bit. I believe both Surface Pros (one and two) can run it. My computer can run VS, but can't run the emulator, because that takes at least four GB of ram and your CPU has to be able to do certain things (VSync, for example). However, you can simply debug on your dev unlocked phone (which is easy to do).
  • Abhishek sir! Saw you at NDTV Profit's Gadget Guru show (here in India) Thanks for supporting Microsoft's platform. Those guys rarely mention WP.
  • I hate that you need to provide screen shots for every resolution your app supports.  My 2 apps require Bluetooth connections to the Pebble watch for the app to look like it works..  Good images are only availabe from the actual phone devices.  In my case I have a 720p HTC 8X and a WVGA Lumia 822 phone so I do not have a good way to provide the WXGA resolution image other than the emulator showing my nonfunctional app. I took the 720p and resized it to the WXGA specifications in photoshop and the image looked good just like the app but it was rejected for the WXGA screen shot. I am looking for a cheap Lumia 928 since I am on Verizon so I can take screen shots from it. I probably would continue to use the Lumia 822 for my regular phone since for me it is the perfect size.
  • You may be doing something wrong with the resizing because I also had an HTC phone but used the "save for web" in illustrator to specify the WXGA dimensions and never had certification issues. I used the store submission form to resize for all other supported resolutions.
  • So how did Words With Friends ever get approved? It crashes constantly, has trouble logging in, and is in general the worst app I have ever seen. The only times my phone has ever locked up completely were times I was playing (or trying to play) wwf.
  • 2 other ones. Make sure you have contact info in the app for users and if you're going to play background music check that no other music is already playing.
  • One advice. Don't develop applications for Windows Phone and Windows RT. Balmer used to say "Developers, Developers, Developers..." now he screwed us. It is btter to learn Java and develop Android applications and dont care about stupid rules like it used to be with Windows Mobile. Or just focuse on development enterprise applications for Windows XP and Windows 7.
  • Roflmao for Android, XP, Java and so on
  • win xp lol you serious ?
  • I was contractor for Barclays Capital until September. They were using XP and I don't think it changed sience then. Corporations don't like new Microsoft products. There is no way they will swith to Windows 8 without Start menu.
  • You are one seriously confused individual.
  • Or, i dunno, get windows 8 you stubborn mule! Jesus people....
  • You forgot to mention Vista! While you're at it, why not 95 too LOL!
  • Where do people like you come from? Microsoft are massively developer centric. How on earth did theyy screw you? (well not you, as you clearly are not a developer - i can tell just be the drivel you write). Don't answer that, we know if will be some more codswallop. Compare Eclipse to Visual Studio. Java to C#. The app cert process and the stringent guidelines you have to follow, like read the article. Its great that they are so adamant on standards so users don't get crashes, don't get apps flattening the battery (although 1 or 2 have slipped through). Compare that to the virus laiden software that ended up in the Google play store! Honestly mate. Step away from the keyboard and stop joining in with the other morons who blindly bash MS based on some juvenile point of view. MS most defintely don't screw developers. MS more than anyone (and Ballmer) knew/knows its all about them.
  • I like C# and Visual studio. I just don't like Windows (Phone) Store rules. For examle I had a contract to develop WP application, but the company requested exit button and block the back button. Microsoft refused my application because of this, so the company moved to Android and haven't paid me. Microsoft used to be developer centric, but it isn't anymore. Now they wants to be like Apple. Home user friendly and don't care about developers and corporations.
  • haha LOL!  
    Which MOUNTAIN are you living under??
  • If you want to make a career out of it, you have a point. I see 0 job adds for WP but plenty for the other 2. This really has to change in order for MS to get moving with this platform. Also in many ways MS, do not make it easy for devs on WP. But for me, its a fun hobby.
  • The localised description one isn't true. Both my apps are listed in all markets with an English only description.
  • Localized descriptions only apply to the languages your app supports, not the countries it's released in. For instance, you can have an app released in Italy but have only English declared as a supported language, in this situation you will only need an English description. However, if you declare Italian as a supported language, then you will need to write a description in Italian (I think this may apply even if the app isn't released in Italy).
  • Yes, it is purely the supported cultures that determine that.
  • The cert process doesn't care about how well an app behaves functionally. As long as it does not crash for the scenarios they test, which will be very few for a complicated app, then it will pass. This is why there are many poor apps around. The cert rules are quite basic really and I think provide a good foundation, but they are not a quality bar as such. They have also become more relaxed in the last 12 months mainly in the policy area, to allow more market impact so WP can thrive. If a dev cannot manage screenshots, then I would question their abilities.
  • Very simple and useful tips