I am having the same issue.
Developing with Unity 5.0.2f1 (32-bit) for Windows and Vuforia 4.2.3 for Unity/Mobile devices.
Testing on a Nexus 5 and Transformer Tf300, Android 4.4.4. Both devices are showing the same issue.
I have attached screenshots demonstrating the problem.
SC_1 - build working correctly
SC_2 - build NOT working correctly, normal map covers screen rather than appearing on model
The only difference between the builds was the shader on the material. For SC_1, the shader was Mobile/Diffuse. For SC_2, the shader was Mobile/Bumped Diffuse.
The problem appears with the following shaders (haven't tested them all, only those listed):
The problem also appears with a custom shader I wrote, involving a normal map and specularity.
The problem doesn't appear with mobile/diffuse and legacy/diffuse shaders. However, normal maps are crucial to improving the look of my low poly models. Any help would be appreciated!
**As a side note, the problem also occurs with the Vuforia sample projects, if the material shaders are changed to anything with a normal map.