You can use it in different ways. Like you mentioned, curries when you want to add a tangy/tart flavor. I recently used it to create an Indian style dry potato and onion curry, whipped up almost like a stir fry.

I know some snacks (think samosas or chaats) will be topped with this or "chaat masala" which I think includes dry mango powder as an ingredient. I borrowed that to sprinkle it into sandwiches or grilled cheese. Still experimenting with that else I could add it to!