Building Mobile Semantic Web Apps with Punya

Half-day tutorial at The 19th International Semantic Web Conference (ISWC 2020).

Mobile devices have become ubiquitous in today’s society, with functionality ranging from straightforward calendars and messengers to sophisticated mHealth and augmented reality apps. In this half-day tutorial, we will introduce Semantic Web and Linked Data practitioners to the world of mobile app building through Punya, a drag-and-drop visual programming environment based on MIT App Inventor that incorporates Jena and other semantic technologies. The goal of Punya is to democratize the ability to ​consume​, ​produce​, and ​act on Linked Data. Participants in this tutorial will gain knowledge of how to build their own apps leveraging JSON-LD to integrate Linked Data from the web. No prior knowledge on mobile app development will be required. The first portion of the tutorial focuses on quickly prototyping mobile apps using traditional create, read, update, and delete actions on a Linked Data repository. The second part will explore newer distributed Linked Data technologies, such as integration with the SOLID platform, device-to-device interaction via the Internet and Web of Things, and lightweight reasoning through technologies like OWL 2 RL. Tutorial attendees will increase their knowledge and skills of (linked) data-driven mobile app development and a greater sense of how to build distributed apps that leverage Linked Data.


This tutorial is intended for anyone interested in using semantic technologies and linked data on smartphones. No previous experience with mobile development is necessary to participate in this tutorial.


In this tutorial we will introduce Punya, a drag-and-drop programming platform for building semantic web-enabled mobile apps. The tutorial will begin with an introduction to the Punya interface and mobile app design. We will then proceed to build an example application that produces and consumes Linked Data graphs in JSON-LD format. In the second half of the tutorial, we will introduce more advanced tools for mobile apps, including integration with Social Linked Data (SOLID), the Constrained Application Protocol extension for Linked Data Platform (LDP-CoAP), and rule-based reasoning with OWL 2 RL. Participants will then be allowed to explore each of these topics at their own pace.


  • 0900-0945: Session I: Introduction to Punya and building basic apps
  • 0945-1030: Session II: Data-driven apps by consuming and producing Linked Data
  • 1030-1100: Coffee break
  • 1100-1130: Session IIIa: Brief overview of advanced technologies (SOLID, LDP-CoAP, reasoning)
  • 1130-1230: Session IIIb: Independent activities (SOLID, LDP-CoAP, reasoning)


Participants should bring a laptop with Google Chrome, Mozilla Firefox, or Apple Safari preinstalled as well as a phone or tablet. Android devices are required. The organizers will provide some devices for those without a phone or tablet, or those who typically use an iOS device.


Evan Patton

Affiliation: MIT App Inventor

Evan Patton image

Evan Patton did his Ph.D. work at Rensselaer Polytechnic Institute, where he studied applications of Linked Data and Semantic Web in the context of mobile devices, which included developing a mobile wine agent using OWL DL reasoning and a suite of tools for analyzing performance of reasoners on mobile devices. While working on his Ph.D., he also spent time as a visiting student at MIT working on Punya, a distribution of App Inventor focused on democratizing access to Linked Data resources. Evan led the integration of Jena into Punya during this time. Now, he leads the development team of the MIT App Inventor project and is involved in a number of efforts to improve its data processing capabilities.

As the lead developer of MIT App Inventor, Evan has organized and proctored workshops for people interested in app development of all ages from middle school to working adults, often working with 30 or more participants. He is also a regular contributor to App Inventor communities providing insights on complex app building issues. He has presented at venues around the world including conferences in Hong Kong and at the International Committee of the Red Cross in Geneva, Switzerland. Additional organizational experiences include the annual App Inventor Summit as well as MoDeST, a workshop at ISWC 2015.

Floriano Scioscia

Affiliation: Information Systems Laboratory, Polytechnic University of Bari, Italy

Floriano Scioscia image

Floriano Scioscia has earned his Ph.D. in 2010 at the Polytechnic University of Bari (Italy), where he is an Assistant Professor since 2018. His research interests include knowledge representation and reasoning for mobile and pervasive computing, service discovery in ubiquitous wireless networks, semantic-enhanced cyber-physical systems and blockchain frameworks. He has co-authored 20 articles in international peer-reviewed journals and over 50 papers in international conferences and workshops.

Since 2011, Floriano Scioscia has been teaching in Master’s and Ph.D. courses at the Polytechnic University of Bari, including Web Languages and Technologies, Formal Languages and Compilers, and Blockchain and Distributed Ledger Technologies.

William Van Woensel

Affiliation: NICHE Research Group, Dalhousie University, Canada

William Van Woensel image

William Van Woensel received his Ph. D. of Computer Science in 2013 at the Vrije Universiteit Brussel (Belgium). He is currently a Postdoctoral Fellow at Dalhousie University (Canada). His research interests lie at the crossroads of Knowledge Representation and Reasoning (KRR), Machine Learning and Mobile Computing applied to Health Informatics. This includes expressive rule-and ontology-based reasoning applied to clinical decision support, and how health informatics can benefit from the mobile deployment of these technologies.

William acted as the Scientific Program Chair of the International Joint Conference on Rules and Reasoning (RuleML+RR), London, UK, 2017. He co-organized the Mobile Deployment for Semantic Technologies (MoDeST) workshop at ISWC 2015, together with Evan Patton and Roberto Yus. He has many years of experience in teaching a range of graduate-level CS courses, including graduate courses for the Health Informatics program.