There is a new Capability Detection tool in the Windows Phone Developer Tools October update that you can run to determine the capabilities of a DLL or Xap files. Here is a post build step that I added to a WP7 project to list the capabilities that are explicitly needed for an application:
set CAPDETECT=%ProgramFiles(x86)%\Microsoft SDKs\Windows Phone\v7.0\Tools\CapDetect\pushd %CAPDETECT%@echo Detecting Capabilities of "$(ProjectDir)$(ConfigurationName)"CapabilityDetection.exe Rules.xml "$(Pr ...
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