Map the custody chain
List every moment a parcel changes hands or state: created, labelled, assigned, picked up, in transit, out for delivery, delivered, failed, returned. Each one becomes a recorded event, never an edit.
Courier & Last-Mile · Field Workforce · Solution Method
Courier Messenger & Parcel Tracking
Real-time GPS of every messenger, a QR chain of custody for every parcel, and proof of delivery that ends disputes.
A corporate document and parcel courier in Dhaka ran 30–35 messengers on phone calls and paper sign-off sheets. Management could not see where a messenger was, which parcels he was carrying, or prove a delivery when a client asked. This research sets out the solution we designed for that operation, and the method behind it: turn every hand-off into an evidenced event, use the phone as the tracker, work offline first, and let the system watch for exceptions. The method applies to any courier, document-runner or field-staff team.
LiveGPS of every messenger
QRChain of custody per parcel
4-wayProof: OTP · sign · photo · GPS
45Working days to go-live
The problem
A courier that cannot prove a delivery.
In most courier and document-messenger operations the parcel's story lives in people's heads. A dispatcher hands a messenger a bundle, the messenger rides off, and the office learns what happened only when he calls, or when a client complains. Four things hurt most:
No visibility. Nobody knows where a messenger is, how many parcels he holds, or which are late.
No evidence. A paper signature cannot show where or when a parcel changed hands, so "I never received it" is hard to answer.
No early warning. A stuck messenger, a phone switched off or a parcel left at the wrong address is discovered hours later.
No numbers. Performance, failed deliveries and returns cannot be measured, so they cannot be managed.
The fix: every hand-off becomes evidence, with who, where, when and proof recorded on the messenger's phone.
The method
Six moves from paper sheets to provable delivery.
The phone is the tracker
Messengers are people, not vehicles. Their Android phone gives GPS without extra hardware, and an adaptive interval keeps battery and data low. Tracking runs only between check-in and check-out.
Evidence at every hand-off
A QR scan and GPS point at every step. At delivery: receiver OTP by SMS, on-screen signature, photo and distance from the pin. The operator makes each one mandatory per parcel type.
Offline first
Dhaka has dead zones: basements, lifts, crowded towers. Everything is recorded on the phone with its real timestamp and synced when the signal returns, so the history is never broken.
Exceptions become alerts
Nobody watches a map all day. The system does: geo-fence entry and exit, delivery far from the pin, tracking silence, low battery, over-speed and SOS reach the right supervisor.
Ship on a proven core
Background GPS, QR scanning, live maps, SMS and reporting already run in the field on our fleet platform. Reusing them turns a risky build into a 45-working-day rollout.
The solution
Two apps, one secure core, a clear chain of custody.
Messenger app (Android): check-in with selfie and GPS, assigned parcels grouped by stage, QR scanning, one-tap status updates, delivery proof, navigation, SOS and, optionally, a push-to-talk walkie-talkie.
Operations dashboard (web): a live map of every messenger, the parcel desk with printable QR labels, assignment and reassignment, geo-fences, alerts, reports and role-based access.
Secure core: an encrypted API with per-device tokens, batched GPS ingest, an alert engine, an append-only event log and automated daily backups.
The parcel journey is the product. Each parcel has a unique tracking ID and a configurable status flow (Created, Assigned, Picked Up, In Transit, Out for Delivery, Delivered), plus Failed, Returned, Cancelled and On Hold, each with a reason.
Every step records parcel, messenger, time, GPS and proof. A scan of the wrong parcel or at the wrong stage is refused. Reassigning a parcel keeps the previous messenger in the history. Custody is never lost, and any parcel's record prints as a proof-of-delivery certificate.
One screen answers the manager's question: where is each messenger, what is he carrying, and what state is each parcel in?
Click a messenger to see his profile, live position, parcels and today's route. Click a parcel to see pickup, movement, delivery and proof. Status is calculated automatically: Available, Assigned, On Delivery, Completed, Offline. Nobody has to update it by hand.
Engineering decisions
Tracking that is accurate, light on battery, and honest.
The two hardest parts of phone-based tracking are Android killing background apps, and battery drain. We answer both with a foreground service, a guided permission set-up (including brand-specific steps for Xiaomi, Oppo, Vivo and Realme), and an adaptive GPS interval:
| Situation | Recording rule | Upload |
|---|---|---|
| Moving | Every 30 seconds or 50 metres, whichever first | Batched every 1–2 minutes |
| Stationary | Every 3–5 minutes | Batched |
| Scan, pickup, delivery, SOS | Immediate high-accuracy fix | Sent at once |
| Checked out | No tracking at all | — |
| Estimate | Value (10-hour shift) |
|---|---|
| Battery | About 2–4% per hour of duty on a mid-range Android phone |
| Mobile data | About 30–60 MB per messenger per month, plus about 150 KB per delivery photo |
| GPS accuracy | 5–15 m outdoors, 20–50 m indoors or in dense blocks. Poor fixes are filtered from routes. |
| Storage | About 2–3 GB of GPS history per year for 35 messengers |
| Maps | OpenStreetMap: no API charges. Google Maps: optional, billed by usage. |
A stale position is never shown as live. The dashboard says "last seen 14 min ago", and a tracking-interrupted alert fires when a checked-in messenger goes silent.
Beyond the brief
What else a messenger operation gains.
Push-to-talk walkie-talkie
Hold to talk, release to send. The dispatcher reaches the team or a group with no calls and no call charges, even with the screen locked.
SOS with escalation
Live location streams until the alarm is closed. If nobody acknowledges it, the alert escalates to the next supervisor by SMS.
Over-speed & low-battery alerts
Catch unsafe riding on motorcycles, and a dying phone before tracking goes dark rather than after.
Fake-GPS & phone-health checks
Detect mock-location apps, GPS switched off, airplane mode or revoked permissions, so location records can be trusted.
Receiver tracking link
An SMS with a link to watch the messenger approach, no app needed. It cuts "where is my parcel" calls.
Client portal & COD
Corporate clients book pickups and download proof of delivery. Cash-on-delivery is reconciled per messenger each day.
Smart dispatch
Suggest the nearest available messenger with the lightest load, and put multi-drop routes in a sensible order.
People & performance
Attendance, conveyance and incentives from GPS, expense claims from the app, and a monthly messenger scorecard.
Rollout
Live in 45 working days, with a prototype on day 10.
- WD 1–5Mobilise & designWorkflow workshop covering fields, statuses, proof rules and roles. Screen designs approved.
- WD 6–10Working prototypeLive map and parcel desk on demo data, and a first messenger APK with check-in, background GPS and parcel list.
- WD 11–25Core buildParcel lifecycle, QR labels and scanning, OTP, signature and photo proof, offline sync, messenger status, geo-fences, SOS.
- WD 26–33Reports & hardeningEleven reports with Excel, CSV and PDF export, audit log, retention rules, and security and device testing.
- WD 34–40Field UATReal parcels run in parallel with the old process. Tracking intervals are tuned on the operator's own phones.
- WD 41–45Go-liveData import, dispatcher training, app roll-out to every messenger, and hypercare.
Where the method applies
Any team that carries something and must prove it arrived.
Courier & document messengers
Corporate letters, cheques, contracts and tender documents where proof of receipt matters.
E-commerce last mile
Riders with many drops a day, COD collection and customer tracking links.
Pharma & medical reps
Samples and cold boxes, visit proof by GPS and photo, and territory geo-fences.
Banks & insurers
Card, statement and document delivery with OTP-verified handover.
Field sales & service
Visit verification, route history, attendance and expenses in one app.
Security & patrol
Checkpoint QR scans, patrol routes, SOS and push-to-talk.
FAQ
Questions operators always ask.
Can a messenger's phone be tracked while the screen is locked?
Yes. The app runs an Android foreground service during duty hours, which keeps recording location with the screen locked or another app open. Tracking starts at check-in and stops at check-out.
What happens when the messenger has no internet?
Locations, QR scans, status changes, photos and signatures are stored on the phone with their original time and GPS, and upload automatically when the connection returns. The route history stays complete.
How much battery and mobile data does GPS tracking use?
With the adaptive interval, roughly 2–4% battery per hour of duty and 30–60 MB of data per month, plus about 150 KB per delivery photo.
How is delivery proved?
By any combination of QR scan, a one-time code sent to the receiver by SMS, an on-screen signature, a delivery photo and the GPS distance from the delivery pin. The operator chooses which are mandatory per parcel type.
Does it need GPS hardware or Google Maps fees?
No GPS hardware is needed, because the messenger's Android phone is the tracker. The dashboard map can run on OpenStreetMap with no API charges. Google Maps is optional and billed by usage.
Can one messenger carry many parcels, and can parcels be reassigned?
Yes to both. Each parcel keeps its own status and proof, and a reassignment keeps the previous messenger in the custody history.
Will it scale beyond 35 messengers?
Yes. GPS uploads are batched and history is indexed by messenger and time, so 100+ messengers and thousands of parcels a day need server capacity, not redevelopment.
How long does it take to go live?
About 45 working days on a proven platform, with a working prototype by working day 10.
বাংলায় সংক্ষেপে
কুরিয়ার ও মেসেঞ্জার ট্র্যাকিং সিস্টেম: পদ্ধতি
ঢাকার একটি কর্পোরেট ডকুমেন্ট ও পার্সেল কুরিয়ার প্রতিষ্ঠানে ৩০–৩৫ জন মেসেঞ্জার ফোন কল আর কাগজের সই-খাতায় কাজ করতেন। কোন মেসেঞ্জার কোথায় আছেন, কার হাতে কোন পার্সেল, আর ডেলিভারি আসলে হয়েছে কিনা, তার কোনো প্রমাণ ছিল না। তাদের জন্য আমরা যে সমাধান ডিজাইন করেছি, এবং তার পেছনের পদ্ধতি, এই রিসার্চে তুলে ধরা হয়েছে।
পদ্ধতির মূল কথা: পার্সেলের প্রতিটি হাতবদল একটি রেকর্ডেড ইভেন্ট, যেখানে থাকে QR স্ক্যান, সময় আর GPS। মেসেঞ্জারের নিজের Android ফোনই ট্র্যাকার, আলাদা GPS ডিভাইস লাগে না। ইন্টারনেট না থাকলেও সব ফোনে জমা থাকে, নেট ফিরলে sync হয়। ডেলিভারির প্রমাণ হিসেবে প্রাপকের OTP, স্ক্রিনে সই, ছবি আর লোকেশন নেওয়া হয়। জিওফেন্স, SOS, ওভার-স্পিড, লো-ব্যাটারি অ্যালার্ট সুপারভাইজারের কাছে নিজে থেকেই যায়। ম্যাপে OpenStreetMap ব্যবহার করলে কোনো API খরচ নেই।
প্রমাণিত প্ল্যাটফর্মের ওপর তৈরি হওয়ায় পুরো সিস্টেম ৪৫ কার্যদিবসে চালু করা যায়, আর প্রোটোটাইপ পাওয়া যায় ১০ দিনে। কুরিয়ার, ই-কমার্স ডেলিভারি, ফার্মা রিপ্রেজেন্টেটিভ, ব্যাংকের ডকুমেন্ট ডেলিভারি, ফিল্ড সেলস বা সিকিউরিটি প্যাট্রোল, যেকোনো মাঠকর্মী দলের জন্য এই পদ্ধতি কাজে লাগে।
Run a messenger team? Let's make every delivery provable.
If your riders, messengers or field staff carry something that must arrive, the method on this page fits your operation.
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