Polyfence documentation

Quickstart

Three peer surfaces — Mobile SDK, Embedded library, Server API. Pick your platform below: install, add a zone, start detecting.

$ flutter pub add polyfence

import 'package:polyfence/polyfence.dart';

await Polyfence.instance.initialize();

final zone = Zone.circle(
  id: 'office',
  name: 'London Office',
  center: PolyfenceLocation(latitude: 51.5074, longitude: -0.1278),
  radius: 200,
);

await Polyfence.instance.addZone(zone);
await Polyfence.instance.startTracking();

// Listen for enter/exit events
Polyfence.instance.onGeofenceEvent((event) {
  print('${event.type} zone: ${event.zone.name}');
});

Source on GitHub: polyfence-core · polyfence-embedded

API reference

Key concepts

Zones

A geographic area (circle or polygon) that triggers events when a device enters or exits. Create via the dashboard, import as GeoJSON, or use the API. No limit on zone count during early access.

On-device detection

On mobile, all geofencing runs on-device using the native Kotlin/Swift engine (polyfence-core). On IoT hardware, the polyfence-embedded C library evaluates coordinates locally. Both paths fire events on the device with no positions sent to Polyfence — use these when you need a strict on-device guarantee. The server-side evaluate API below is the alternative for devices that can’t run the C library.

SmartGPSMobile

The mobile SDK adapts GPS polling based on user activity (walking, driving, stationary) and proximity to zones. Saves battery while keeping detection latency under 50ms.

Embedded / IoTNew

Run geofence checks on ESP32, STM32, Raspberry Pi, or any device with a C11 toolchain. The polyfence-embedded library is under 100KB compiled with zero external dependencies. Sync zones via REST API, evaluate coordinates locally.

Evaluate APIIoT

Server-side point-in-polygon checks for IoT devices that don’t run the C library. Send a device ID and coordinates, get back zone events and current zone membership. Positions are discarded by default, retained only when you opt in to hosted history via the per-account retention toggle (GET /v1/account/retention / PATCH /v1/account/retention). The setting is echoed on every GET /v1/devices/{deviceId} row so your code can mirror it.

View API reference

API keys

Authenticate REST API calls with an x-api-key header. Keys are scoped ( zones:read, zones:write, zones:delete ) and stored as SHA-256 hashes.

Get API key

Privacy posture

Polyfence applies different defaults to different kinds of data — here’s each.

Positions

Positions are evaluated and discarded — not stored. Hosted history is opt-in per device when you need it (PATCH /v1/account/retention).

Anonymous telemetry

Anonymous platform metrics — never identifiers, never coordinates. One line of code disables it.

Your account info

Standard B2B SaaS PII — email, billing. Identical to what Stripe or Vercel hold about you.

Polyfence collects zero PII and zero identifiable data about your end users. Full breakdown on the privacy page.

Platform support