For example, your app icon would be blue and black and your logo on printed shirts would be red and black.
In a world where people's attention span is about 5s, having different color schemes would not only contribute to reduce your target's attention span but also create confusion that would annihilate whatever your target remembers about your brand.
Consumers typically accepts different color schemes when having B&W vs color. See the following examples of good color branding.
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