Distances between objects
Photoshop has a useful feauture — it shows the distance between currently held object and adjacent one, when you hold Control.
(I coldn't capture these annotations on video, sadly).
AI just doesn't.
It can detect similar gaps between objects, show offset from current position, but not distances to neigbours.
And it even doesn't show offsets when you use snap to grid (with Smart guides on).
Please, make snaps great again.
Omar Guillermo commented
How to get this to the front page? It's kind of ridiculous that photoshop supports this and illustrator doesn't!