How can I make invitations in german?
What word in german works as "Let's" or "What about" in English?

Question

Answer

You can also use the 'wir' form, but invert the subject and verb. This is extremely common in addition the two options above. Examples:

Gehen wir ins Kino.
Sehen wir einen Film an. 
Kochen wir Frühstück.

You can also add "mal" after the subject and verb to add a flavor of politeness to the suggestion.

Gehen wir mal ins Kino. 
Las uns mal ins Kino gehen. 
Was hältst du davon, mal ins Kino zu gehen.

This is a bit colloquial, but very common.

Answer

I would say for example "Lass uns, (ins Kino gehen)" or "Was hältst du davon, (ins Kino zu gehen?)".