# FieldSim - Protocol Simulator — Industrial Protocol Simulator

> Industrial Protocol Simulator (iPhone/iPad app by Alexandr Garlock Development House LLC.)

- Source: https://appshunter.io/ios/app/fieldsim-protocol-simulator/id6819095224 (this page in markdown: same URL + `.md`)
- Developer: [Alexandr Garlock Development House LLC](https://appshunter.io/developer/353093375)
- Category: Developer Tools, Utilities
- Price: $9.99
- Age rating: 4+
- Requires: iOS 27.0 · 2 MB
- Languages: American English
- Released: 2026-10-14
- Data updated: 2026-10-15

## What is FieldSim?

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.

## Chart rankings

- #54 in Top Paid · Developer Tools (US App Store)

## Is FieldSim safe?

Not enough ratings yet to assess FieldSim.

## Is FieldSim legit?

FieldSim - Protocol Simulator appears legitimate, with a few gaps. The AppsHunter Legitimacy Score for FieldSim is 65 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 1 release)

### 1.0 — 2026-10-14

No release notes.

## More apps by Alexandr Garlock Development House LLC

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- [Fidget Prestige](https://appshunter.io/ios/app/fidget-prestige/id6794064981)
- [Pulse Puff](https://appshunter.io/ios/app/pulse-puff/id6794459229)

All apps by Alexandr Garlock Development House LLC: https://appshunter.io/developer/353093375

## Related topics

[pocus simulator](https://appshunter.io/ios/topics/pocus-simulator) · [g1 simulator](https://appshunter.io/ios/topics/g1-simulator)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-15.*