Bells and whistles,
Definition of Bells and whistles:
Largely unwanted, or unwarranted, features added or supplanted to a product to make it look better against competing products. In software industry, bells and whistles are often added to force a new (but barely different or improved) version on the captive customers (who have invested considerable amount of money and time in acquiring and learning previous versions).
Attractive additional features or trimmings.
Meaning of Bells and whistles & Bells and whistles Definition