Difference between 'zu Hause' and 'nach Hause'

What is the difference between zu Hause and nach Hause?

means being at home

often used with verbs such as sein, bleiben, for example:

Ich bleibe morgen zu Hause.

Bist du schon zu Hause?

used when there is a movement towards home

often used with verbs such as gehen, fahren, kommen, for example:

Ich gehe jetzt nach Hause.

Wann bist du nach Hause gekommen?