FAQ #15653, published on 2017-10-17
How to deal with a "Duplicate resources" error when generating an Android App?
This error occurs when your project contains two resource files with the same name (the file extension are different).

[raw/app_android] <project_path>\Android\Generation\res\raw\Customers.wdd
[raw/app_android] <project_path>\Android\Generation\res\raw\Customers.xdd

Error: Duplicate resources
:mergeReleaseResources FAILED

This is a limitation of the Android resource manager and one of the two files must be renamed.

There is one special case that must be dealt with a bit differently when the analysis name appears in the error message (as Customers.wdd above). In such a case, simply remove the .wdd filename in the "Integrating files" step while generating the Android app. The .xdd file is always integrated in the Apk, it cannot be removed.