1. Introduction

2. Background and literature review

3. The VRRO Platform

3.1. Functionalities

In the initial launch of VRRO, the primary objectives were to provide users with a rich and interactive experience quickly and to gather user feedback for future enhancements. The platform's core modules, including the interactive map, the social module, the virtual tour gallery, and the blog module, have been comprehensively implemented. These features offer users a complete experience, emphasizing ease of use and immediate access to Romania's cultural and natural beauty.

While the main modules of VRRO are operational and provide a full user experience, specific areas have been identified for future development. The platform currently lacks automated content moderation for user-uploaded content, advanced image compression, and request queuing processes. Additionally, the implementation of a custom-built ID verification system using computer vision technology is planned but not yet realized. Future enhancements also include the development of animated virtual tours, incorporating video uploads, frame capturing, and a corresponding viewer. The foundational tools for this feature are in place, but full implementation awaits.

Therefore, the initial version of VRRO stands as a comprehensive yet evolving foundation, designed to adapt and expand based on user feedback and technological advancements. The aim is to continually refine and enhance the virtual tourism experience, making VRRO a dynamic and responsive platform in the virtual tourism landscape.

3.1.1. Virtual tours gallery

One of the VRRO's primary features is the VT gallery, allowing users to filter and search tours automatically ordered by popularity. Additionally, an alternative viewing mode is provided through an interactive map, granting users a geographical perspective of the showcased locations. These virtual tours are available as non-immersive VR, mobile augmented virtuality (AV), allowing sensor input, and fully immersive mobile VR, with the help of smartphone VR Mounts. The mobile VR functionality offers a highly immersive [20] and low-interactive experience, allowing users to delve into static 360° VT of diverse Romanian tourist attractions.

Figure 2. Four major pages of the VT module: the map (a), the gallery (b), the single tour view (c), and tour creation form (d).

Figure 2. Four major pages of the VT module: the map (a), the gallery (b), the single tour view (c), and tour creation form (d).

Another pivotal feature is the VT creation toolset. Beyond just viewing, registered users are endowed with the capability to upload and design their own virtual tours. In the creation process, the challenge of finding and entering the tour location is solved with the use of a map submodule with a single pin serving as input. The pin's position can be adjusted via direct drag on the map or location search (using a string that represents the name or address).

The VRRO platform is designed for accessibility across various devices, using the Panolens.js [21] library to ensure cross-compatibility and optimal performance. This library, complemented by custom CSS rules, guarantees that the virtual tour views are correctly displayed on desktop interfaces, mobile devices, and mobile VR equipment. The platform's multi-platform approach is integral to providing users with a flexible and immersive virtual tourism experience, catering to diverse preferences, whether it's through traditional desktop interaction, the portability of smartphones and tablets, or the immersive capabilities of mobile VR devices.

The settings menu allows users to change their tour viewing experience by selecting their preferred control and view mode. The control options include sensor-based navigation using a gyroscope for a more immersive experience, particularly on mobile devices, or traditional mouse and touch inputs for desktop and standard mobile use. For the view mode, users can choose between normal, cardboard, or stereoscopic views. The fully immersive mode is accessible on mobile devices by combining sensor data as the control setting with either the cardboard or stereoscopic view modes. These customizable settings ensure that users can enjoy a seamless virtual tour experience on the VRRO platform, regardless of their device or preferred mode of interaction.

Figure 3. The mobile VR view is accessible through the selected settings.

Figure 3. The mobile VR view is accessible through the selected settings.

3.1.2. Social module

The platform's commitment to fostering community engagement is evident in its social component. Users are empowered to create personal profiles, facilitating interactions such as comments, likes, and direct messaging. Ensuring user trust, all interactions are meticulously stored in compliance with the General Data Protection Regulation [22].

The social module of the VRRO platform encapsulates a real-time chat feature. By integrating SignalR [23], a powerful real-time web functionality library for ASP.NET, the platform delivers instant messaging capabilities through a persistent, bidirectional connection between the server and connected clients.

The social module is accessible to registered users. However, interactions are limited to befriended users. Only those who made a public presence through posts or comments have accessible profiles and can receive friend requests.

Figure 4. The social module's main pages: friend list (a), chat (b), and chat list (c).

Figure 4. The social module's main pages: friend list (a), chat (b), and chat list (c).

3.1.3. Blog

Complementing its virtual tour offerings, the VRRO platform also serves as a hub for tourism-related content through its Blog section. Both individual enthusiasts and institutional partners can contribute articles centered on tourism themes. To encourage reader engagement, functionalities such as commenting and voting through liking articles have been integrated.

The integration of the CKEditor [24] library in the blog's text editor allows for rich content creation. Users can easily style text and incorporate images, facilitating the production of visually appealing and well-formatted articles.

Figure 5. The informational blog also plays a major role in user engagement and interaction. The figure presents the article list (a), single-article view (b) and associated comments (c) and the article creation form (d).

Figure 5. The informational blog also plays a major role in user engagement and interaction. The figure presents the article list (a), single-article view (b) and associated comments (c) and the article creation form (d).

3.1.4. User engagement

To encourage user activity and reward engagement, the gamification module introduces elements such as badges for active users. It also promotes popular articles or tours, ensuring that quality content gets the recognition it deserves.

The visitors are encouraged to become a part of the community through the welcoming messages on the site’s landing page and encouraging messages on buttons that lead to account-creating actions or VT-creating actions if logged in.

VRRO employs a gamification strategy that rewards users with badges for various levels of engagement. These badges include the Community Badge, awarded for engaging in multiple posts or chats; the Explorer and the Informer Badges, for users who actively create gallery or blog posts, respectively; and the VIP Badge, for those whose posts exceed in popularity. This system not only incentivizes user interaction but also acknowledges and celebrates the contributions of active members within the VRRO community.

Figure 6. Users are encouraged to take an active part in the community (a, b) and are rewarded (c).

Figure 6. Users are encouraged to take an active part in the community (a, b) and are rewarded (c).

3.2. Architecture

VRRO is designed with a combination of distributed, Three-Tier, and Model-View-Controller (MVC) architectures. This integration ensures scalability, maintainability, and efficient data processing, with a focus on distributed functionalities across various services and components.

The Three-Tier architecture provides a structured approach by dividing the application into three distinct layers: the presentation layer, the business logic layer, and the data layer. Within this structure, the platform’s architecture is built on a robust and scalable .NET Core framework [25], integrating a Model-View-Controller (MVC) design pattern that divides the application into logical units to enable efficient development, testing, and maintenance. Each functional module (Social, VT Gallery, Blog, Map) consists of models, views, and controllers, using specific services or libraries that facilitate their functionality. Entity Framework Core [26] is used in the backend for object-relational mapping, ensuring smooth data transactions with our Azure-hosted distributed database [27].

3.2.1. Presentation Layer

The presentation layer primarily consists of Views from the MVC architecture, focusing on user interface and interaction. These Views are dynamically rendered based on the data and logic provided by Models and Controllers located in the business logic layer. This layer is fundamental in defining the user's initial and ongoing interaction with the platform.

The design is minimalist and elegant, providing a user interface that is visually appealing, with a straightforward and intuitive interface. This design choice helps new users quickly learn how to use the platform, improving their overall experience.

Additionally, the presentation layer has a responsive design. This means it works well on a variety of devices, from desktop computers to mobile phones and tablets. The platform is robust and easy to understand, with content that is easy to read and helpful input assistance. While the platform works in many different scenarios, it is especially well-suited for basic input methods. The platform is designed to be inclusive, offering text alternatives for non-text content, enabling its transformation into various accessible forms.

Overall, the presentation layer of VRRO delivers an accessible, user-friendly, and aesthetically pleasing experience, reflecting the platform's commitment to making Romania's cultural and natural heritage globally accessible and adhering to various accessibility standards [28].

3.2.2. Business Logic Layer

The core of VRRO's functionality lies in its Business Logic Layer. This layer is primarily composed of Controllers, the functional components of the MVC architecture that manages the flow of data within the application (MapController, BlogController, GalleryController, ProfileController, etc.). They interact with models to process business logic, handle user requests, and determine the data presented in the views.

Central to this layer are the Entity Models, intricately mapped to the database tables (e.g.: Post entity model). These models are responsible for more than just data handling; they enforce business rules, including access protocols, formatting rules, and error message management. Complementing these are the Domain-Specific Models, which define the data structure, outline relationships, and establish business rules (e.g.: GalleryPost and BlogPost, which extend the Post entity model).

The layer is further enhanced by specialized services, that manage specific processes or business rules, such as authentication, content management, and the logic behind user interactions (e.g.: ChatHub, FileManagement service, etc.). An integral part of this layer is also the client-side scripts, which include integrations with client-side APIs and support for synchronized real-time services, ensuring a smooth and responsive user experience.

3.2.3. Data Layer

In the data layer, the VRRO Platform utilizes Entity Framework Core [26] as its Object-Relational Mapping (ORM) system. This layer consists of database tables that correspond to Entity Models. Although these Entity Models are part of the business logic layer, they are crucial for the data layer as they directly map to the database, facilitating seamless data management and interaction between the application's business logic and its data storage.

The platform utilizes a relational database model, which organizes data into tables corresponding to entities or to relationships between them. This model is particularly advantageous for its ability to efficiently handle large volumes of data while maintaining strong data integrity and consistency. Compared to other database models, relational databases offer superior flexibility in querying and data manipulation, making them ideal for complex applications like VRRO that require robust data management and sophisticated query capabilities.

3.2.4. Cross-Layer Accessibility of Cloud Services

The VRRO platform is characterized by a distributed architecture, a design that spreads its functionalities across multiple computer networks to enhance efficiency and reliability, using Azure cloud hosting [29].

However, VRRO also integrates a range of external cloud services, each contributing unique functionalities to the platform. The following paragraphs present the specific cloud services and functionalities integrated within each of the Three-Tier layers, illustrating how they collectively contribute to the robust and flexible nature of the platform.

In the Presentation and Business Logic Layers, the platform utilizes Google Maps API [30] for dynamic map displays, enriching the user's navigational experience with geographical context. Additionally, the Panolens.js [21] library plays a crucial role in providing immersive virtual tour views, ensuring a seamless and engaging user experience across different devices.

At the Business Layer, the platform's core functionalities are supported by a suite of services. Microsoft's Identity Service ensures secure user authentication and management, while Google OAuth [31] integration offers a streamlined sign-in process. Real-time communication is facilitated by Azure SignalR [23], essential for the platform's chat feature. Furthermore, the SendGrid Emailing Service [32], integrated within the Azure framework, handles email communications.

Within the Data Layer, which includes Hosting and Infrastructure, Azure Files storage [27] is employed for efficient file management. The Azure Database [27] is used for data management, offering scalability and robust performance. The Microsoft Identity Management platform [33], beyond authentication, also contributes to the management of user data tables.

Figure 7. Architecture and components diagram: a structured overview of the VRRO Web Application, detailing its interactions with external Cloud Services and between different modules within the application.

Figure 7. Architecture and components diagram: a structured overview of the VRRO Web Application, detailing its interactions with external Cloud Services and between different modules within the application.

4. Empirical Study

4.2. Results

The results included answers from 31 users, 9 female (29%) and 22 male (71%), of ages ranging from 22 to 42 years old, all past or present visitors of Romania, with the intention of traveling within Romania in the future. Users rated their familiarity with web technologies highly, with a mean score of 4.5 out of 5, while immersive technologies familiarity ratings had a mean score of 3.7 out of 5.

Figure 8. User demographics: age (a) and gender (b), and reported familiarity for web (c) and immersive (d) technologies.

Figure 8. User demographics: age (a) and gender (b), and reported familiarity for web (c) and immersive (d) technologies.

The devices used for accessing the platform were preponderantly mobile (21), and the most used operating system iOS. Four participants used both mobile and desktop devices in their experience, and 9 only desktop devices.

Figure 9. Preferred platform access. (a) 70% of surveyed users preferred access by mobile devices; (b) the preferred operating system is iOS (41.9 %).

Figure 9. Preferred platform access. (a) 70% of surveyed users preferred access by mobile devices; (b) the preferred operating system is iOS (41.9 %).

4.2.1. Activity

We categorized our users based on their level of interaction with the platform from a pool of 31 participants. A total of 10 users, representing 32.3% of the sample, were identified as 'Active creators.' Within this group, 60% (6 users) created tours, 20% (2 users) wrote articles, and another 20% (2 users) contributed to both the gallery and blog posts. These individuals were not only frequent visitors but also actively engaged with the platform's features.

A smaller segment, consisting of 4 users (12.9%), showed 'Low interaction,' participating minimally and preferring to engage through voting or commenting on posts rather than creating content.

Among the active 14 users, 14.3% (2 users) never voted, 71.4% (10 users) voted multiple times, and 14.3% (2 users) voted once. For commenting, 21.4% (3 users) did so once, 28.6% (4 users) commented more than once, and 50% (7 users) never commented at all. 28.6% (4 users) befriended other users and only 14.3% (2 users) of the active users received badges, a reward for high levels of activity.

The 'Visitors,' who primarily used the platform to view content, constituted the majority, with 17 users making up 54.8% of the total participants. This group's interaction was characterized by significantly less content creation and interaction compared to the other groups.

Figure 9. User classification by activity (a) and user preferences of viewing virtual tours (b).

Figure 9. User classification by activity (a) and user preferences of viewing virtual tours (b).

29% of the participants favored a traditional approach of VT viewing, engaging exclusively with basic panoramic views on desktop interfaces, aligning with the 9 users that used exclusively desktop devices.

A significant majority, approximately 68%, utilized mobile devices to access the tours, indicating a preference for more immersive experiences. Within this mobile user segment, a small proportion, roughly 10%, experimented with augmented virtuality, which integrates the physical environment with digital overlays through device sensors. A larger portion, 48%, opted for a virtual reality format, suggesting a preference for a fully immersive digital experience.

Notably, 23% of participants were inclined towards a hybrid approach, engaging with both basic panoramas and VR formats. This indicates a non-exclusive, exploratory interaction with the available technological modalities.

4.2.2. Engagement

The platform's commitment to delivering a seamless and engaging user experience is reflected in the ratings provided by our diverse user base. To capture the essence of this experience, we have analyzed the UES scores alongside the ratings for open-access modules and specialized features accessible to active users. This analysis not only sheds light on the overall satisfaction but also allows us to discern patterns across various user segments.

Table 2. Summary of User Engagement Scale scores.

Table 2. Summary of User Engagement Scale scores.

Factor	Focused Attention	FA 1	FA 2	FA 3	Perceived Usability	Aesthetic Appeal	Reward Factor	UES (Overall)
Score	2.97	2.29	3.23	3.39	4.56	3.70	3.97	3.81

The lower scores in the FA factor of the UES for the VRRO platform align with the platform’s primary function as an informational and educational tool. The platform's minimalist aesthetic, characterized by a simple color scheme and a straightforward interface, facilitates easy navigation and efficient information consumption. However, this design approach, while effective for its intended purpose, does not inherently promote deep immersion or a sense of escapism, which are typical contributors to higher FA scores.

The content and interaction style on VRRO, including article viewing, virtual tour exploration, and chatting, are primarily structured for information exchange rather than immersive engagement. The VR mode, offering static image views, provides a basic level of virtual experience but lacks interactive or dynamic elements that could lead to higher levels of user absorption. This focus on information delivery over immersive interaction is reflected in the FA scores, particularly in the lower ratings for the first statement, "I lost myself in this experience."

Future enhancements to VRRO could aim to increase user immersion and engagement, by incorporating engaging narratives, interactive tutorials, and enhanced VR experiences. However, any such enhancements should be carefully balanced with VRRO's core informational and educational objectives, ensuring that the platform remains true to its primary purpose while enriching the user experience.

The survey questions also assessed users' intent to use the platform for travel-related activities and their likelihood to recommend it to others. These responses were used to create an endurability index, mirroring the concept from the long-form UES, which reflects users' long-term engagement and potential for recommendation.

Table 3. Engagement endurability scores.

Table 3. Engagement endurability scores.

Question Categories	Average Score
Commemorate Travels	4.10
Connect with Travelers	3.65
Pre-travel Information	4.06
Inform Other Travelers	4.10
Future Platform Use	3.94
Recommend to Friends	4.23
Drive Index	3.98
Endurability Index	4.05

The Drive Index, with a calculated value of 3.98, serves as a quantitative measure of users' immediate motivation to engage with the VRRO platform. This index is derived by averaging responses to four key questions that assess users' intentions to use the platform for specific activities: commemorating travels, connecting with travelers, gathering pre-travel information, and informing other travelers. This high score suggests that the platform successfully meets user needs and interests.

The Endurability Index, with a value of 4.05, reflects the long-term potential of user involvement and the likelihood of users recommending the platform to others. It is calculated by averaging the Drive Index and responses to the next two questions, regarding future platform use and the propensity to recommend the platform to friends. The score underscores the platform's capability to not only attract users initially but also retain them over time, indicating a strong potential for building a loyal user base and fostering community growth.

Another section of the user feedback questionnaire focused on user satisfaction with specific modules of the platform (the Map, the Blog, and the VT Gallery). Overall ratings for the open-access modules—Map, VT Viewer, and Art Viewer—indicate a consistently positive experience, with scores exceeding 4 out of 5 (Table 4). This suggests a high level of satisfaction with the platform's core functionalities available to all users.

The specialized features, such as Article Creation, VT Creation, and Chat, evaluated only by our 14 active users, also received favorable ratings, with the Article Creation module standing out with the highest scores. This reflects the platform's ability to cater to content creators with tools that are both functional and user-friendly.

When segmenting the data, nuanced variations in ratings based on users' expertise with web and immersive technologies are observed. Notably, participants who reported high technological familiarity tended to rate the modules slightly higher than the others, pointing to a correlation between technological familiarity and user satisfaction.

Table 5. Overall experience ratings.

Table 5. Overall experience ratings.

Module	UES	Open access modules	Advanced features	Endurability
Rating	3.81	4.06	3.76	4.05

4.2.3. The influence of digital literacy on experience

In the initial stage of our analysis, we concentrated on the distribution of user engagement scores (UES), technology familiarity assessments, and ratings of the open-access modules (accessible for both visitors and authenticated users) —datasets encompassing information from all 31 participants. The selection of these data sets for normality testing was driven by our aim to understand the underlying patterns of user interaction with the platform.

Before presenting the normality of these distributions, we present an overview of overall ratings by user engagement factors and technology familiarity. This summary (Table 6) provides a baseline understanding of how users with different levels of digital literacy perceive various aspects of the platform, setting the stage for a deeper analysis of distributional characteristics.

Preliminary analysis of the overall ratings suggests a pattern where participants with higher familiarity with web and immersive technologies tend to report slightly higher engagement scores across the individual factors of the User Engagement Scale, as well as overall the UES. Similarly, the ratings for the Virtual Tour (VT) Viewer, Article Viewer, and Map functionalities also appear marginally higher among these users.

By assessing the normality of these distributions, we aim to validate the appropriateness of the statistical methods used for further comparative analysis. The following table encapsulates the results of the Shapiro-Wilk test and key descriptive statistics, providing a snapshot of the data's distribution.

Table 7. Data Normality and Descriptive Statistics for Key Study Variables.

Table 7. Data Normality and Descriptive Statistics for Key Study Variables.

Variable	Shapiro-Wilk W	p-value	Average (x̄)	Std. Deviation (S)
UES	0.9749	0.6616	3.8118	0.5137
VT Viewer	0.8253	<0.001	4.0323	1.016
Article Viewer	0.7897	<0.001	4.129	1.0565
Map	0.8174	<0.001	4.0323	1.0796
Web Familiarity	0.5904	<0.001	4.5484	0.85
XR Familiarity	0.875	0.0018	3.7097	1.1603

The comparative analysis of user engagement and module ratings across different levels of technology familiarity revealed no statistically significant differences (Table 8). The UES scores, which reflect user engagement, showed a slight tendency for higher engagement among users familiar with immersive technologies, but this did not reach statistical significance. Similarly, the ratings for the open-access modules did not differ significantly between users with high or low familiarity with web and immersive technologies. The effect sizes were generally small, indicating minimal practical differences in perceptions between the groups. This suggests that familiarity with the technology did not markedly influence the users' engagement or their perception of the platform's modules. This may also imply that these factors may not have a substantial impact on the user experience within the sample studied.

4.2.4. Qualitative insights

To draw qualitative insights into users' experiences, four open-ended questions were posed to assess their candid opinions on the platform's usability and features. Users expressed a strong affinity for the platform's core functionalities, particularly the ease of creating and viewing virtual tours and the informative content provided by the map feature and blog posts. The platform is seen as a valuable tool for travel enthusiasts, especially those interested in virtual reality and photography, with many users indicating they would recommend it to close friends and family who share a passion for travel.

However, users also highlighted areas for improvement, suggesting a need for a more engaging user interface and additional functionalities such as video uploads and social media integration. Technical issues such as slow loading times and navigation difficulties were noted as annoyances that detract from the overall experience. Despite these challenges, the concept of 'pre-visiting' destinations resonated well with users, pointing to the platform's potential as a planning tool for explorers and adventurers. These insights suggest that while the platform's concept is well-received, focusing on design elegance, technical refinement, and community-building features could significantly enhance user satisfaction and engagement.

5. Conclusions

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