There should be a way to prompt a system-specific ‘alert’ or ‘confirmation’ modal, like this in xcode: https://developer.apple.com/documentation/uikit/uialertcontroller . Similar to push notifications described here: https://www.defold.com/manuals/push/ , but only triggered within the app (so the app does not require push notification permissions).
If this is already available, please link me to the documentation and I will close this question, thanks!
No, there is no support for native system alerts, but it should be possible to add via a native extension. Do you need it to be a native dialog or could it work with one created as a Defold gui?
A defold GUI to act as an alert or confirmation would be fairly straightforward to make, but I think it’s a good idea to leverage system level components whenever possible to create a user experience that’s familiar and predictable for the player. It also eliminates the need to create an additional art asset (along with corresponding animations, button colors, feedback, etc.) that matches the game theme.
For games, this kind of prompt is not what you want. You want alerts which match the game theme. There are several community resources already made which can handle popups.
This would be useful for alert about system updates, for example. Just sharing my interest on this feature here 
I think the consensus was that system alerts should be styled to fit the game and by that it’s better to implement as a normal GUI popup and not an actual native dialog of some kind. Are you actually interested in native popups?