A torque tool app that pairs, calibrates, and logs every job.
AM Wrench connects Bluetooth-enabled torque tools to mobile — displaying live torque readings, enforcing calibration intervals, logging every fastening to a job record, and alerting when spec is missed. We built the Bluetooth pairing layer, the job logging system, and the technician mobile app.
In precision engineering — automotive, aerospace, manufacturing — under-torqued fasteners cause failures.
In precision engineering — automotive, aerospace, manufacturing — under-torqued fasteners cause failures. Over-torqued ones strip threads. Manual torque logging with paper logs is error-prone, auditable but unreliable, and impossible to review in real time.
The tools exist — Bluetooth-enabled torque wrenches are standard in professional environments. What didn't exist was an app that connected them, enforced specs per job, and produced an audit log that passed quality certification requirements.
AM Wrench came to Fusionwave with a hardware partnership, a QA certification requirement, and 12 weeks to an engineering trade show demo.
Precision UX for precision tools.
We embedded with two engineering teams for a week of field observation. The UX constraint: technicians wear gloves, work in poor lighting, and cannot lose focus on the fastening. The app had to provide real-time feedback (pass/fail) without requiring the technician to look at the screen mid-job.
Bluetooth precision. Audit-grade logging.
Flutter handles iOS and Android with native Bluetooth LE integration. Each tool connection is maintained with a reconnect-on-loss protocol — the app recovers within 3 seconds if signal drops. All fastening events are logged locally and synced to the cloud when connected.
What ships in the product.
Bluetooth tool pairing
Pairs with Bluetooth LE torque tools from major manufacturers via a guided radar scan and auto-reconnect protocol.
Live torque display
Real-time torque reading with min/max spec overlay. Green/amber/red status with audio and haptic feedback.
Job record logging
Every fastening is logged with timestamp, torque value, tool ID, and technician ID. Tamper-evident audit trail.
Spec library
Pre-configured torque specs for common fastener types, vehicle models, and equipment profiles. Technician selects job type at start.
Calibration tracking
Tool usage counter triggers calibration reminders at configured intervals. Out-of-calibration tools are flagged and blocked from new jobs.
Offline operation
All readings log locally when off-network. Syncs to cloud when connectivity returns. No data loss in signal-poor environments.
Job reports
Auto-generated PDF job completion reports — fastening log, pass/fail summary, tool IDs — ready for quality records.
Multi-tool support
Technicians can pair up to 4 tools simultaneously. Each tool's readings are tracked independently with separate spec profiles.
Team management
Supervisors see team-level job logs, tool status across the fleet, and calibration schedules from a web dashboard.
Production-grade from week one.
We chose the boring, battle-tested options where it mattered and innovated where it gave the product a real edge.
The AM Wrench app caught three out-of-spec fastenings in the first week that our paper logs would have missed. That's three potential warranty claims avoided.
What it took.
- Bluetooth reliability in industrial environments. Metal-heavy environments reflect and absorb Bluetooth signal. We implemented a connection quality monitor with automatic channel-hopping and a reconnect-on-loss loop that maintains the session without losing the active job record.
- Audit-grade tamper evidence. Log entries that can be edited are worthless for certification. We implemented append-only logging with server-side hash chaining — each record includes the hash of the previous entry, making silent modification detectable.
- Glove-compatible UX. Standard 44px touch targets fail with work gloves. We built 72px minimum targets, audio confirmation for every fastening event, and a haptic pass/fail pattern — technicians can complete a job without looking at the screen.
- Multi-manufacturer Bluetooth protocol. Torque tool manufacturers use proprietary BLE profiles. We built a tool adapter layer with protocol decoders for the four major manufacturers — new manufacturers can be added via a JSON protocol definition without app updates.
What changed.
A walk through the product.
Key screens, detailed.
A closer look at the core user flows built for this product.
Building something like AM Wrench?
AM Wrench connects Bluetooth-enabled torque tools to mobile — displaying live torque readings, enforcing calibration intervals, logging every fastening to a job record, and alerting when spec is missed. Send us a brief and we'll scope it within 24 hours.