Working with Windows Phone devices with 256 MB of memory
This article provides an introduction to the information on this wiki that will help you prepare your apps for Windows Phone devices with 256 MB of memory, such as the Nokia Lumia 610.
Windows Phone 7.5
Windows Phone now offers a 256 MB memory configuration to phone manufacturers. Nokia introduced its first such phone at Mobile World Congress 2012: The Nokia Lumia 610. The purpose behind the introduction of this memory configuration is to enable more affordable Windows Phone devices, with the goal of expanding the Windows Phone to more markets and more consumers.
Research by Nokia and Microsoft suggests that the vast majority of Windows Phone apps will run unchanged on 256 MB phones. However, while your apps still have a 90 MB working set available to them on 256 MB phones, once a working set goes over 60 MB paging will occur.
It will therefore be good practice to ensure that your apps work within a 60 MB working set, thereby ensuring the best UX on any Windows Phone device. Nokia and Microsoft have put together a collection of best practice tip to help you do this. Following these tips will help keep your app's memory requirements to a minimum and give you the best opportunity to create an app for all Windows Phone owners.
Of course, implementing best practices and knowing that you app’s memory overhead fits optimally within the memory parameters of the 256 MB phones are not quite the same thing. Fortunately, an update to the Windows Phone SDK (currently available as a technical preview) comes with features to help you discover information about your app’s memory use (and there are some home grown solutions you can add to your apps too).
Check out the Techniques for memory analysis of Windows Phone apps.
There will be some app’s that simply won’t fulfil the requirements of 256 MB phones: it might be a game or an app that relies heavily on background tasks to deliver its functions. In these cases you’ll want to make sure it’s not available to owners of 256 MB phone and you do so by Opting your app out from Windows Phone with 256 MB.