# Mobile AR: User Evaluation in a Cultural Heritage Context
## 4 Discussion  
The use of mobile AR in CH contexts was first implemented close to the beginning of the millennium, as can be seen in the MARS project [24] and in the ARCHEOGUIDE project [25]. Back then, the user needed to carry a set of heavy devices and these systems were considered mobile. However, the concept of mobile has changed greatly: currently, mobile systems need to be much lighter (e.g., handheld devices or glasses). These forerunner projects were followed by other research solutions related to mobile AR applied to CH sites aiming at exhibition enhancement, reconstruction, and exploration purposes [26]. Previous  
Figure 11: Low level of agreement (in the presented scale from 1 to 5, disagreement corresponds to Levels 1 and 2) related to errors of positioning of the virtual model while using DinofelisAR.  
Figure 10: Low level of agreement (in the presented scale from 1 to 5, disagreement corresponds to Levels 1 and 2) related to the oscillation of the virtual model while using DinofelisAR.  
studies during the last decade, e.g. the use of AR children to imagine certain artifacts and situations related to historical contexts [27], have shown us the perceived enjoyment and usefulness of AR technology in CH contexts [28] as well as enhanced customer value [29]. The presented study provides data that confirm the particular timeliness of mobile AR usage among cultural sites.  
The subjective data collected provide indications of a great acceptance of AR apps applied to cultural heritage, regarding to fun and learning (e.g., the ability to better describe the Forum characteristic). These very positive results, where users affirmed they will use the system on their personal smartphones, suggest that the use AR may attract more visitor.  
According to the results obtained, the performance issues identified by users did not appear to interfere with their willingness to use mobile AR in CH. However, since the technology used was a novelty for most participants, it may have had the advantage of surprise. For this reason, and because AR technology is becoming increasingly popular, in future implementations, the presented issues must be minimized or fixed, in order to follow the evolution of technology.  
Future research directions should provide understandings related to users' involvement during AR experiences. The current study, as well as previous studies related to AR implementations, did not cover evaluations of the sense of presence when experiencing AR and this lack of information led us to an unaware of how to create more engaging experiences with AR in CH. One way to do it would be the use of this technology to stimulate more human senses, such as audio, touch, and smell. A deep understanding of the users' intention to use AR technology to accomplish successful approaches should also be considered.  
Regarding to technical implementation, future applications should provide better tracking behavior than the extended tracking used for the current study. Considering the willing of visitors to walk around and explore the site when experiencing the AR app, it would allow the user to walk around and explore the virtual elements, instead of staying in one place and just rotating the device 360 degrees. In fact, humans are more used to exploring their surroundings by walking around, getting close to elements we want to see, and not staying at one place and rotating. Other improvements may include investigating the suggestions and issues reported by users, such as finding a solution to avoid the sun on the screen, having a bigger device to better observe the virtual elements, or adding avatars and animations to better understand the size of the augmented elements.