Decentralized identifiers (DIDs) and verifiable credentials (VCs) are emerging concepts for creating verifiable self-sovereign digital identities for people, organizations and Internet of things (IoT). In this demo, we share the implementation details and experiences for realizing a decentralized IoT data authorization framework [9] with a Pebble tracker, an in-house built trusted GPS tracking device with 4G connectivity and sensor technologies. Our implementation demonstrates great flexibility and tremendous advantages towards building decentralized and global-scale IoT applications. To the best of our knowledge, this is the first real-world demo for enabling decentralized IoT data authorization with DIDs and VCs.