The objective of the systematic review was to identify the elements that compose authoring tools to create applications based on immersive technologies. To do so, the following research questions (RQ) were posed:

RQ1: What design, technical or technological aspects should be considered in the construction of authoring tools that generate immersive applications?

These research questions were aligned with the PICOC method (Population, Intervention, Comparison, Output, Context) proposed by Petticrew and Roberts [8] to define the scope of the review:

Population (P): Authoring tools oriented to teaching immersive technologies.

Inclusion Criteria (IC):

IC1: The work is in English.

The search strategy was implemented in the SCOPUS database due to its broad coverage of publications in diverse knowledge areas and indexing of most relevant publications in computer science. Based on PICOC elements, the "Authoring tool" was identified as the main term to be included in the search string. Additionally, terms related to immersive technologies were selected; for instance, "augmented reality," "virtual reality," and "mixed reality." The final search string was:

TITLE-ABS-KEY ("authoring tool" AND ("augmented reality" OR "virtual reality" OR "mixed reality"))

To guarantee the inclusion of relevant works that answered the research questions, the following quality assessment criteria (QC) were established:

QC1: Does the work include architectural aspects of authoring tools?

After applying the quality assessment criteria, nine (9) main studies were chosen as part of the systematic review out of the thirty-one (31) works selected in the previous stage.

Categories of authoring tools with immersive technologies that are relevant for university teaching were identified. They include:

Web-based tools: Tools like WebAR [9] and SimpleAR [11] allow teachers to create immersive applications to support their teaching processes. These tools are usually accessible from web browsers and allow collaborative content creation.

The diversity of identified authoring tools, from web-based solutions to those incorporating specialized augmented and virtual reality SDKs, evidences the evolution and maturity of the field. This variety not only eases the creation of immersive content but also allows university teachers to select the most appropriate tool according to their specific pedagogical needs and available technological resources.

Graphic editors: Most immersive authoring tools include graphic editors that allow teachers to create content visually; editors in [11], [13], [15] stand out due to their graphical interface. These editors are usually intuitive and ease the creation of immersive experiences.

Therefore, authoring tools in immersive technologies provide a set of elements and features that facilitate the creation of interactive educational content.

In this review, no explicit references to didactic considerations in the construction of authoring tools with immersive applications were found. However, some works addressed aspects related to evaluation within didactics, such as the inclusion of assessments in the activities created by the tool [10].

In the following sections, results will be discussed in detail and additional analysis and conclusions based on the findings of this systematic literature review will be presented.

The analysis of the proposals revealed fundamental considerations about architecture and design: 1) Use of SDKs and libraries for immersive content generation [9], [10], [11], [13] 2) Implementation of databases as content repositories [10], [11]; 3) Dichotomy between web systems [9], [10], [11], [12] and native applications [13]. Additionally, important aspects such as content sharing and distribution, use of external resources, connectivity requirements, and multi-user support should be considered.

Several significant elements were identified: 1) Various editing interfaces, from flow designers [14] to real-time editors [15], [16]; 2) Import of pre-designed resources and resource libraries. Aspects such as activity flow definition, access to resource libraries, and content preview must be considered.

A set of considerations that will guide the definition of the authoring tool's architecture was identified, namely: 1) JSON (JavaScript Object Notation) logical content structure, non-relational databases [11]; 2) Content distribution (client-server approach) [12]; 3) External resource management; 4) Choice between desktop or web-based application; 5) User and role management; 6) Immersive technology for the tool.

Regarding functional requirements of the authoring tool, the following considerations are proposed: 1) Content structure (flows or sequential screens); 2) External resource management; 3) Activity adaptation to immersive technologies; 4) Content editing and export.

Based on the proposal by Cortes et al [18], the following aspects are suggested: 1) Selection of subject and learning theme; 2) Definition of activity type and environment; 3) Teacher's role as companion [19].

Based on the proposals of [19] and [20], a selection of activities adaptable to immersive technologies that can be implemented through authoring tools is presented. While this selection is not exhaustive and could be expanded based on new academic contributions or technological advances, it represents a starting point to include other types of activities in the future. The proposed activities adaptable to immersive technologies are Debate, Inquiry, Role-playing, Simulations, and Laboratory. Additionally, pedagogical aspects that should be considered in the construction of the authoring tool were identified: 1) Establishment of learning objectives; 2) Curricular adaptation; 3) Evaluation and feedback; 4) Accessibility and universal design.

A reference framework can be defined as a set of interconnected components that provide coherence, collaboration, and reuse options. It enables identifying common elements, creating consistency, and offers a group of standards, policies, and patterns to achieve an objective by using it [21].

The proposed reference framework for the construction of authoring tools with immersive technology applications is made up by four main components: 1) a conceptual model, with two subcomponents (didactic and immersive technologies authoring tools); 2) software architecture of immersive technologies authoring tools (Views and practices); 3) Roles (software development professionals, teachers, and students); 4) Processes. Fig 1 presents a graphic representation that integrates these elements to define a reference framework for the construction of authoring tools with immersive technology applications based on the systematic review.

Fig 1

It's worth highlighting that the proposed framework and the previously presented components should be interrelated through a series of processes, which will provide an ordered guide to define the elements presented in the reference framework, e.g., defining didactic aspects, defining functionalities of the authoring tool, and defining architecture design could be considered.