Brick and mortar companies have websites. Some have adapted those websites for mobile (m.com). Some are compelled to have both a m.com and a mobile application (m.app).
It raises the question of how unique the experience should be in each of those channels. Are there agreed "norms?" Should there be overlap in features/content in each experience?
Let's make this concrete. Take a restaurant chain. They sell food. They sell atmosphere where you eat that food. Simplistically, a restaurant's digital-self can offer: