Modbus TCP Pro vs Curly

Modbus Reader & Writer is a powerful and intuitive Modbus TCP tool designed for professionals. Built for installers, HVAC technicians, engineers, and system integrators who need a fast and reliable way to test, read, and write Modbus registers directly from their iPhone. Whether you work with heat pumps, PLCs, energy meters, or industrial controllers, this app gives you full control over Modbus TCP devices — anytime, anywhere. Key Features • Modbus TCP Connectivity • Connect to any Modbus TCP device using IP address and port • Configurable Unit ID (slave ID) • Read Registers • Holding Registers (Function Code 03) • Input Registers (Function Code 04) • Support for multiple data types and values • Write Registers • Write Single Register • Write Multiple Registers • Instant feedback and clear error reporting • Designed for Testing & Debugging • Ideal for commissioning and troubleshooting • Perfect for field testing without a laptop • Compatible with Modbus simulators and test environments (e.g. Node-RED) Who Is This App For? • HVAC installers and service technicians • Industrial automation and PLC engineers • Energy and building management professionals • System integrators and commissioning engineers • Developers testing Modbus-based systems Reliable & Efficient • Fast and stable connections • Clear and actionable error messages • Clean, focused interface — no unnecessary complexity • Optimized for real-world professional use Modbus Reader & Writer is your mobile Modbus toolbox — ready for every installation, test, and service intervention.

Curly is a native REST API client built for iOS and iPad. Designed for developers who need a fast, lightweight tool to test and debug APIs directly from their device. Features: - Send GET, POST, PUT, PATCH, DELETE requests - Edit query params, headers, auth, and request body - Inspect responses with JSON syntax highlighting - Filter JSON responses with JSONPath expressions - Organize endpoints into collections with emoji icons and nested folders - Drag-and-drop requests between folders - Import Postman and Bruno collections - Import requests by pasting cURL commands - Copy requests as cURL for sharing - Environment variables with autocomplete, inline preview, and bulk import across environments - Pre-request and post-response scripts - View response headers, status codes, timing, and size