Geofencing REST API for iOS & Android

Fencemaker doesn't ship native mobile SDKs — integration is done directly through the REST API. This keeps the client footprint small and puts you in control of location capture and background execution, using each platform's native location services to gather coordinates and Fencemaker's REST endpoints to evaluate geofences and deliver events.

Two integration patterns, one API. This guide covers the minimal pattern — your app captures location and POSTs it directly, and Fencemaker evaluates every zone server-side on each ping. If you'd rather register geofences with the OS itself (CLCircularRegion / GeofencingClient) so the device only wakes your app on an actual crossing, see the full native OS geofencing guide — both patterns call the same /api/v1/track endpoint under the hood.

iOS Integration (Swift)

Use CoreLocation to capture device location, then POST updates to the Fencemaker REST API.

import CoreLocation

// Send a location update to Fencemaker
func sendLocationUpdate(deviceId: String, lat: Double, lon: Double) {
    var request = URLRequest(url: URL(string: "https://fencemaker.app/api/v1/track")!)
    request.httpMethod = "POST"
    request.setValue("gfnsr_live_YOUR_KEY", forHTTPHeaderField: "X-API-Key")
    request.setValue("application/json", forHTTPHeaderField: "Content-Type")

    let body: [String: Any] = ["device_id": deviceId, "lat": lat, "lon": lon]
    request.httpBody = try? JSONSerialization.data(withJSONObject: body)

    URLSession.shared.dataTask(with: request).resume()
}

Location capture and background permissions (NSLocationWhenInUseUsageDescription / NSLocationAlwaysAndWhenInUseUsageDescription) are handled entirely by your app via CoreLocation — Fencemaker only receives the coordinates you choose to send.

Android Integration (Kotlin)

Use FusedLocationProviderClient to capture device location, then POST updates to the same REST endpoint.

fun sendLocationUpdate(deviceId: String, lat: Double, lon: Double) {
    val client = OkHttpClient()
    val json = """{"device_id":"$deviceId","lat":$lat,"lon":$lon}"""
    val body = json.toRequestBody("application/json".toMediaType())

    val request = Request.Builder()
        .url("https://fencemaker.app/api/v1/track")
        .addHeader("X-API-Key", "gfnsr_live_YOUR_KEY")
        .post(body)
        .build()

    client.newCall(request).enqueue(object : Callback {
        override fun onResponse(call: Call, response: Response) { /* handle events[] in response body */ }
        override fun onFailure(call: Call, e: IOException) { /* handle error */ }
    })
}

Location capture and background permissions (ACCESS_FINE_LOCATION / ACCESS_BACKGROUND_LOCATION) are handled by your app via FusedLocationProviderClient — Fencemaker only receives the coordinates you choose to send.

What comes back

Every /api/v1/track call evaluates the device against all of your active geofences and returns any entry/exit events inline, in addition to firing configured webhooks:

{
  "device_id": "device_001",
  "events": [
    { "type": "entered", "territory_code": "ZONE-A", "webhook_fired": true }
  ],
  "territories_inside": ["uuid"],
  "response_ms": 12
}

iOS vs Android at a Glance

Consideration	iOS	Android
Location capture	CoreLocation (CLLocationManager)	FusedLocationProviderClient
Background execution	Managed by your app (background modes / significant-location-change)	Managed by your app (foreground service or WorkManager)
Event delivery	Server-side webhook (Slack, Telegram, or custom HTTPS) — not a device callback	Server-side webhook (Slack, Telegram, or custom HTTPS) — not a device callback
Rate limiting	Batch/throttle updates client-side to stay within API rate limits	Batch/throttle updates client-side to stay within API rate limits

Integration Notes

Because there's no SDK, your app owns background location handling, permission prompts, and update throttling directly — Fencemaker's role is the REST API: creating geofences, accepting location updates, and delivering entry/exit events as webhooks. Full endpoint and authentication details are in the API reference; free-tier limits for testing this integration are on the free geofencing API page.