In the few decades that robot vacuum cleaners have existed in, they've certainly advanced. They're not the basic, almost-useless cleaners they used to be. Now, they can vacuum well, mop, build maps of your home, and empty and clean themselves.
The best robot vacuum for one home might be different from another. It all depends on factors like house size or whether you have pets, so before making the decision it's smart to weigh up what's essential and what isn't.
