Location-awareness provides mobile users with topical and personal contents that may increase the appeal of mobile guides in different application fields. Based on the results of seven field studies, this paper identifies factors of usability, utility and user trust that affect the user acceptance of location-aware mobile guides. The results indicate that on-the-move use sets high requirements for ease-of-use and, in particular, ease of taking the services into use. The need for location-aware mobile guides turned out to be occasional, but in many of those occasional usage situations the guides proved extremely useful. The trade-off between privacy protection and effortless use requires careful consideration, even though in these studies the users turned out to be trusting towards the service providers. The results indicate that location-awareness can provide the users with easy-to-use and situationally relevant mobile guides.