FieldSim - Protocol Simulator
Industrial Protocol Simulator
$9.99 · Designed for iPad. Not verified for macOS.
Simulate 11 real industrial & IoT protocols on iPhone — MQTT, OPC UA, Modbus, BACnet, DNP3, EtherNet/IP, SNMP, AMQP, CoAP, HART-IP, LoRaWAN — with built-in test clients.
Fieldsim turns your iPhone into a real industrial and IoT protocol test bench — no extra hardware, no lab PC, no separate test tools.
Fieldsim isn't a mock-up. Every protocol is implemented against its real wire-level specification and verified against industry-standard reference clients and libraries. Real SCADA software, PLCs, and IoT gateways can connect to your iPhone and talk to it exactly as they would to a real field device.
Simulate 11 real protocols:
• MQTT — full broker with multi-topic publish/subscribe
• OPC UA — session/subscription server with a real address space
• Modbus TCP — coils, discrete inputs, holding & input registers
• BACnet/IP — Who-Is/I-Am discovery, ReadProperty/WriteProperty
• DNP3 — link/transport/application layers, Class 0 polling, Direct Operate
• EtherNet/IP — CIP explicit messaging (Get/Set_Attribute_Single)
• SNMP v2c — GET/GETNEXT/SET plus trap notifications
• AMQP 0-9-1 — full exchange/queue/consumer message broker
• CoAP — RFC 7252 with the Observe extension for live push updates
• HART-IP — session-managed Pass-Through with Universal Commands
• LoRaWAN — a real Network Server speaking the Semtech UDP protocol, with AES-128/CMAC frame encryption and authentication
Every protocol, both directions. Each simulator supports multiple simultaneous tags, points, or objects — build out a small virtual plant, not just one sensor. And every protocol also has a matching built-in client on the Client tab, so you can test your simulator (or any other real device on your network) without installing a second app or opening a terminal.
Built for real testing, not demos:
• Live, scrollable activity logs for every simulator and client
• Save and reuse connection presets per protocol — host, port, credentials, and protocol-specific settings
• Automatic detection of your iPhone's network address, so external clients always know where to connect
• Configurable value patterns (random, sine wave, ramp, static) for realistic simulated data
Who it's for:
Automation and controls engineers validating SCADA/HMI integrations, QA teams testing IoT gateways and protocol converters, product developers building device firmware against real-world protocols, and students or instructors learning how industrial protocols actually work on the wire.
Fieldsim is iOS-native, built entirely on Apple's Network framework — fast, lightweight, and works over Wi-Fi with any device on the same network.
Ratings & Reviews
The developer, Alexandr Garlock Development House LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Alexandr Garlock Development House LLC
- Size
- 2.6 MB
- Category
- Developer Tools
- Compatibility
Requires iOS 27.0 or later.
- iPhone
Requires iOS 27.0 or later. - iPad
Requires iPadOS 27.0 or later. - Mac
Requires macOS 27.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 27.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © AG Dev House LLC
