Read original post by Abhishek Sur at Daily .NET Tips
Windows Phone is gradually getting matured day by day. Considering the current situation, the Windows Phone environment gives a restrictive environment where app developers are restricted to do certain things if not specified beforehand. The developer cannot use Library, Camera, Sensors or even memory at sometimes if not defined beforehand.
A Windows Phone App is limited to use 150 MB at max. But sometimes it is well a requirement to have more than this limit at least for high spec devices to run. To solve this problem, you can define a capability on your App to ensure you have high availability of application memory.