iphone: Building error precompiling app_prefix.pch

Did you move your [Project Name]_prefix.pch file ? If you moved it to say, a subdirectory of the project's parent, you need to open up the target Build settings for each of your targets by double clicking on them, do a search for "pch" in the build settings, and update the path to the .pch file.

For example, if you moved your .pch file to a subdirectory "Core" which is in the project parent, then you'd change "[Project Name]_prefix.pch" in the build settings to "Core/[Project Name]_prefix.pch".

Try to change the buid setting of the target in project propertys:

Change the option Precompile prefix header to "NO"