Bluetooth Fingerprint Attendance MVP App

Job ID: 40565541

Budget: $250 – $750 USD

Description:

I’m building a very focused Android MVP for farm worker attendance using a Bluetooth fingerprint scanner.

Core idea

A farm manager uses an Android phone + external Bluetooth fingerprint reader in the field.
They:

Select/enter the farm location or block

Connect to a Bluetooth fingerprint scanner

Let workers scan their fingerprint to mark attendance

Enter a daily rate for that session (or per worker)

Sync data to a backend and export CSV/Excel for payroll

I already have a potential Bluetooth fingerprint scanner with SDK/API shortlisted (Android support claimed). I’ll handle contact with the hardware supplier and share the SDK docs and sample app with you.

Scope of work (MVP)
You will:

Android app (native, Kotlin or Java)

Implement Bluetooth connection to the provided fingerprint scanner using the vendor SDK

Fingerprint enrollment flow (link templates to worker records)

Attendance scan flow:

Manager selects/inputs location

Manager enters daily rate

Each scan creates an event: worker, timestamp, location, rate

Basic offline storage (e.g., Room/SQLite).

Sync to a simple REST backend (I’m open to your recommendation: Firebase/Supabase/simple API).

Backend (very simple)

Minimal API for: employees, sessions, attendance events

Ability to export data (CSV/Excel) by date/location for payroll import

Simple admin UI or even just basic endpoints is fine for MVP.

Deliverables

Android Studio project with clean, well‑structured code

Basic documentation on setup, build, and how to run against the scanner

Short written note on any limitations or edge cases

Requirements
Strong experience with Android native development (Kotlin or Java)

Solid experience with Bluetooth / BLE on Android

Must have integrated external hardware via an SDK before (barcode scanner, fingerprint reader, or similar)

Comfortable working from vendor SDK docs and example projects

Familiar with offline‑first patterns (local DB + background sync)

Nice to have:

Previous work with biometrics (fingerprint, face, etc.)

Experience with time & attendance or payroll-related apps

Familiarity with Firebase/Supabase or simple Node/Express/Django backends

How we’ll work
I will provide:

The exact scanner model, SDK package, docs, and sample APK/source from the vendor

A short functional spec and data model

You will:

Propose a brief implementation plan

Start with a paid test milestone: connect to the scanner on Android and prove we can capture a fingerprint event and identify a user

What to include in your proposal
2–3 sentences on your relevant experience with Bluetooth and hardware SDKs on Android

Any links/screenshots to similar apps you’ve built (especially with scanners or biometrics)

Your estimate (in weeks) for:

(a) scanner integration + local prototype

(b) full MVP with backend + CSV export

Your preferred tech stack for the backend (if you will handle it too)