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ADA Patrol

Guard checkpoint and asset-tracking apps

ADA Patrol is a family of Android apps for a Singapore security operator: a guard checkpoint app that turns NFC or QR scans into a photo-logged patrol record, a second variant that resolves each checkpoint to a real address through Singapore's OneMap service, and a separate asset-tracking app that watches for Bluetooth tags in the field.

  • 2025
  • Singapore
  • Android (Kotlin)
  • NFC + QR checkpoint scanning
  • Bluetooth LE asset tracking
  • OneMap reverse-geocoding
Illustration of ADA Patrol

The challenge

A security operator needed proof that a guard actually walked every checkpoint on a round, not just a signed paper sheet at the end of a shift. The app had to work offline at remote checkpoints, capture a timestamped photo at each stop, and produce a log an admin could trust and export. A later variant needed each checkpoint tied to a verifiable street address rather than raw coordinates, and a separate need arose to track Bluetooth-tagged assets in the field independently of the patrol rounds.

Who uses it

Guard
Scans an NFC tag or QR code at each checkpoint, attaches a photo, and moves to the next stop on the round.
Supervisor
Reviews patrol logs, checkpoint photos, and device/site configuration, and exports records as CSV.
Field operator (asset tracking)
Carries the tracking app to log nearby Bluetooth tags with GPS position in the background.

What we built

We built an Android patrol app where a guard scans an NFC tag or QR code at each checkpoint, attaches a photo, and the app writes a local, exportable log; a second variant adds Singapore OneMap reverse-geocoding so checkpoint locations resolve to real addresses for a National Environment Agency round. A separate BLE asset-tracking app scans for iBeacon tags, logs sightings with GPS position, and queues them for upload over a background tracking service.

  • NFC/QR checkpoint scan

    A guard scans an NFC tag or a QR code to register arrival at a checkpoint, with automatic QR detection.

  • Checkpoint photo capture

    Each checkpoint stop can attach one or more photos, which can be moved, reordered, or deleted before submission.

  • Offline-first patrol log

    Checkpoints, photos, and patrol state are written to a local Room database so a round can continue without signal.

  • CSV export

    Patrol and checkpoint data exports to CSV for reporting outside the app.

  • Site/device configuration

    A password-gated settings screen sets device ID, site ID, API endpoint, and photo resolution per installation.

  • Reverse-geocoded checkpoints (NEA variant)

    The NEA variant looks up each checkpoint's GPS position against Singapore's OneMap service to resolve a real address.

  • Bluetooth asset scanning

    The tracking app parses iBeacon advertisements from nearby Bluetooth tags and logs sightings with signal strength.

  • Background tracking service

    A foreground service keeps scanning and GPS ticking while the app is backgrounded, with a watchdog receiver to restart it and a retry queue for failed uploads.

How it works

  1. A guard opens the patrol app and starts a round, or the tracking app begins its background scan.
  2. At each checkpoint, the guard scans the NFC tag or QR code and takes a photo.
  3. The app writes the checkpoint, photo, and (in the NEA variant) a reverse-geocoded address to the local database.
  4. The app syncs the completed round to the backend API, with logs and CSV export available for review.
  5. In the tracking app, detected beacon sightings and GPS fixes queue locally and upload in the background, retrying on failure.
Close-up of the ADA Patrol checkpoint screen with the QR-scan frame and checkpoint list.
Close-up of the ADA Patrol checkpoint screen with the QR-scan frame and checkpoint list.

Every part of the product

  • Patrol app

    Kotlin, Room, ZXing QR, NFC

    Guard-facing checkpoint scanning, photo capture, and offline patrol logging.

  • Patrol app (NEA variant)

    Kotlin, Room, OneMap API

    Same patrol flow with checkpoint locations reverse-geocoded to street addresses via Singapore's OneMap service.

  • Asset-tracking app

    Kotlin, Bluetooth LE, GPS, foreground service

    Background scanning for Bluetooth asset tags, logging sightings with position and queuing them for upload.

How it’s built

The patrol apps keep checkpoint state in a local Room database first and sync to the backend second, so a guard can finish a round with no signal and have it upload once connectivity returns. The NEA variant adds a token-managed OneMap client that exchanges GPS coordinates for a street address at save time, keeping that lookup out of the guard's critical path. The tracking app runs its Bluetooth and GPS work inside a single foreground service with a watchdog receiver and boot receiver, since a tracking app that silently stops scanning after the OS kills it in the background is worse than no app at all; a retry queue on top absorbs the inevitable gaps in connectivity in the field.

  • Android
  • Kotlin
  • Room
  • NFC
  • ZXing (QR)
  • Bluetooth LE
  • OneMap API
  • Retrofit
  • Foreground service

What clients say about working with us

Verified Fiverr reviews from our clients, quoted word for word.

5.0 98 verified reviews · Fiverr Top Rated
Venkey and his team is very responsive and understand the needs very well. Despite the time differences, we have regular and eventful meetings to get project delivered on-time.
wenqi7Singapore · Client on this project
It was awesome working with the Seller, he was patient and delivered a great work. Will always work with him
nitracleUnited States
Really it was a very good experience with this freelancer. He has very clear understanding of our expectations and made a perfect logo for our business. He also made modifications as per the request without any hesitation. Thank you somuch Venzpire for your wonderful support.
happy_vibeIndia
first thing to mention is timely delivery and response. logo color and style was designed well. It is according to our expectations. budget friendly
dnk3201Repeat buyerIndia

Read all 98 client reviews

Questions about ADA Patrol

What does ADA Patrol do?

ADA Patrol is a guard checkpoint system Venzpire built for a security operator in Singapore: guards scan an NFC tag or QR code at each checkpoint, attach a photo, and the app keeps an offline-first, exportable log of the round. A separate app in the same family tracks Bluetooth-tagged assets in the field.

Is there AI in ADA Patrol?

No. Despite 'AI' appearing in an early version's app name, Venzpire found no machine-learning, computer-vision, or language-model feature in the codebase; what looked like an AI endpoint turned out to be a plain configuration and password-sync call. The product is a conventional scan-and-log patrol system.

How does the NEA variant of ADA Patrol differ from the base app?

Venzpire added a Singapore OneMap integration to the NEA variant so each checkpoint's GPS coordinates resolve to a real street address at save time, on top of the same NFC/QR scan-and-photo patrol flow as the base app.

Your product could be next.

Tell us what you are building. Venktesh reads every application himself and replies within one business day.

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