Complementary products (cross-selling)
Recommend other products as complementary to the current product, if they were previously ordered with this product or if they are contained in selected categories. For instance, you may recommend cases, protective glasses, and earphones for smartphones.
Upselling & similar (upselling)
Recommend products with other prices and features, or products of absolutely different types, matching specified criteria. For instance, for a certain smartphone you may recommend other smartphones of different brands with similar functionality.