Facebook is one of the biggest contributors to OpenStreetMap and makes lots of open source software.

I’d like to know more about this.

I’m certainly not trying to be an Apple apologist here, as iMessage has plenty to critique. But it bears consideration that iMessage falling back to SMS is a certain amount of openness, is it not?

Not an unfair complaint against Apple, but ignores Google’s/Android’s problematic “support” for RCS, and in this context of this comment seems to imply that What’sApp isn’t “closed” like iMessage.

apple hates open standards

What about WhatsApp is open?