diff-gui is a web-based dynamic analysis tool for Android applications that provides real-time instrumentation capabilities through Frida integration. The tool features a Flask-based web interface with Jinja templates for rendering and uses Redis as a message queue system for handling operations. It incorporates server-side push technology to deliver real-time updates to users during analysis sessions. The application allows users to enter Android package names and select from available instrumentation modules or create custom modules by adding JavaScript scripts to the modules folder. It includes an integrated development environment (IDE) where users can modify scripts and view results on the same interface. The tool supports both JavaScript-based hooking and native code hooking capabilities for comprehensive application analysis. Users can instrument running Android applications by connecting to devices via Frida, enabling dynamic analysis of application behavior, API calls, and runtime modifications. Setup requires installing Python dependencies, running a Redis server, and deploying the Frida server to the target Android device. The tool verifies proper Frida installation through device connectivity testing before allowing instrumentation operations to proceed.