Reference documentation

Mobile Devices documentation

• How it works
• Webhook documentation

Java documentation

• Java 8 core API
• Java HttpServer package
• Create a Simple Web Server in Java (1) - HTTP Server
• How to Send HTTP Request GET/POST in Java
• Sending JSON data with HttpURLConnection
• Unit Testing with JUnit - Tutorial
• JUnit API

JSON documentation

• JSON website
• JSON Processing - JSR 353: Java API for JSON Processing - Reference Implementation
• JSON Processing API Javadoc
• online JSON viewer

Base64 online decoder

• base64 to hexadecimal or UTF-8