Case Study
Offline First Mobile Modernization: Reducing Data Latency By 99% In Corrections
See how Acme Software transformed a legacy Jail Management System into a ruggedized, offline-first Flutter app, reducing data latency from 12 hours to <30 seconds.
Key Result
Reduced data latency from 12 hours to <30 seconds.
Industry
Hardware
Honeywell CT40 & CT60 Ruggedized Android Devices
Tech Stack
Reduced Data Latency from 12 Hours to <30 Seconds with Offline-First Mobile Architecture
Digital transformation in public safety is often stalled by "hostile network environments"—thick concrete walls and signal jammers that kill connectivity. Acme Software tackled this challenge for a major corrections provider, moving them from a failing web-based system to a ruggedized, offline-first mobile architecture. By leveraging Google’s Flutter framework and engineering a bespoke bridge for Honeywell hardware, we successfully decoupled the frontend user experience from the legacy backend. The result was a mission-critical tool that ensures 100% data integrity, regardless of network status.
The Challenge: The "Connectivity Void"
The client, a major provider of correctional software, faced operational paralysis. Their legacy Jail Management System (JMS) relied on a web-based architecture that required a continuous connection to a monolithic .NET backend.
However, correctional facilities are physically engineered to contain people, which inadvertently makes them excellent Faraday cages.
Physical Barriers
Reinforced concrete walls (>12 inches thick) and steel containment units created "dead zones" covering up to 40% of the facility.
Active Interference
The deployment of Managed Access Systems (MAS) to block contraband cell phones actively degraded the wireless spectrum, causing packet loss for legitimate staff devices.
The Cost of Inaction Because the software failed in these dead zones, officers reverted to paper logs. This created a "Data Latency Gap" of 8 to 12 hours—the time between an incident occurring and the data actually being entered into the system at the end of a shift.
Safety Risk
Command staff had zero real-time visibility into inmate locations during emergencies.
Legal Liability
Paper logs are prone to illegible handwriting and "pencil whipping" (falsifying checks), creating significant litigation risks.
The Solution: A Distributed, Offline-First Architecture
Acme Software implemented an "Evolutionary Modernization" strategy. Rather than rewriting the massive legacy backend, we replatformed the mobile edge into a "Thick Client" capable of autonomous decision-making.
1. The Offline-First Engine (CQRS & Sembast)
We moved away from the standard request-response model. The app assumes it is offline by default.
Battery Optimization
We utilized Sembast, a NoSQL document store running entirely in Dart, to handle sub-millisecond read/write operations locally.
Command Queue
When an officer logs a movement, the data is written instantly to a local sync queue. A background "Sync Engine" monitors network connectivity and processes this queue when a connection is available, utilizing a Last-Write-Wins strategy to resolve conflicts.
Optimistic UI
The interface updates immediately upon user interaction, eliminating "loading spinners" and reducing cognitive load for officers in high-stress environments.
2. Bridging the Hardware Gap (Honeywell Integration)
Standard camera scanning was too slow (3-5 seconds) for mass movements. We needed to access the dedicated laser imagers on the Honeywell CT40/CT60 devices, but the SDK was native Java, not Flutter-compatible.
We utilized Pigeon, a code-generation tool, to create a type-safe bridge between the Flutter UI and the native Honeywell Mobility SDK. This allowed us to:
- Trigger millisecond-fast scans using the hardware laser.
- Read damaged barcodes through scratched plexiglass.
- Open Source the Solution: We sanitized and released this integration as the honeywell_mobility_sdk on pub.dev, benefiting the global developer community.
3. Feature Enablement & Compliance
Battery Optimization
We engineered foreground services to bypass aggressive Android "Doze" modes, ensuring wellness check timers continued running even when the device screen was off.
Legal Compliance
We implemented vector-based signature capture (recording stroke pressure and velocity) and cryptographically hashed the results to meet ESIGN Act and DOJ audit requirements.
Key Results
By shifting the "source of truth" to the network edge, Acme Software delivered a solution that works with the environment, not against it.
99% Reduction in Data Latency
"Time-to-visibility" for inmate movements dropped from 8-12 hours to <30 seconds. In connected zones, updates are near real-time.
60% Faster Headcounts
The optimized hardware integration allows officers to scan wristbands in rapid "burst mode," clearing a pod of 60 inmates in minutes rather than an hour.
100% Audit Compliance
Automated "Proof of Presence" scans and monotonic clock logic eliminated falsified logs ("pencil whipping"), ensuring pilot facilities hit 100% compliance on observation intervals.
80% Less Testing Time
Utilizing the Patrol framework for native automation allowed us to automate complex hardware regression tests, significantly reducing QA overhead.
No Rush! Let's Start With Project Discovery.
Whether you are launching a new vision from scratch or need to inject quality into an ongoing project, our team brings the expertise to make it happen. We build solid foundations from the start.
