In the past years artificial intelligence (AI) has become an important subject for both companies and consumer due to the growth of personal AI assistants and external service robots. It is clear that many aspects of our life are not like they used to be. The fact that every one of us is sooner or later going to incorporate various AI functions in daily routine activities becomes somehow certain. It is not only our home-life that is transforming, but also the way we, as consumers, are going to interact with different product and service providers. In this paper we provide a comparative literature review on the challenges and research topics regarding personal AI assistants and external service robots. While the personal AI assistants intervene more in the private sphere of the consumer, the relation to the external service robots is more distant. The results of our literature review show that the relation between consumer and external service robot is more characterized by interaction, enjoyment and engagement, it is expected to have a parasocial friendship relation between consumer and personal AI assistants. Taking this difference of perspective the two types of AI will be differently involved in the future business and marketing activities of companies.