Region: US / UK | Usage example: Comparing those products is apples and oranges because they serve different needs.

Apples and oranges

Meaning

Two things that are fundamentally different and not directly comparable.

Warns against unfair comparisons.

Origin notes can vary by region and source; this page gives the commonly reported explanation and usage context.

Fruit metaphor referencing obvious differences.

Commonly invoked in educational settings from the early 1900s.