There are 4 types of AI:
- Reactive Machines
- Limited Memory
- Theory of Mind
- Self-awareness
Theory of Mind and Sel-awareness are still in progress. There isn't anything build using it. Google Assistant and Alexa do use some memory but that is only on the individual level to learn patterns. Alexa does not learn from its memory so it cannot be of the type Limited Memory.
I think its Reactive Machine with a part of limited theory concepts.