Been using slideAcross for a bit now and the UX is what's actually won me over.
Most presentation tools give you one path through a deck. This one lets you branch. Layer content underneath a slide, drill down when someone asks a question you half expected, and the whole thing still feels calm rather than chaotic.
Voice control is the bit I didn't expect to like as much as I do. Being able to move through layers without breaking eye contact with the room changes how a presentation actually feels to deliver.
Not saying it reinvents presenting. But the drill down and layering solve a real problem, and once you've used it that way it's hard to go back to a straight line of slides.