▸Example Flurry call (the "before")
import Flurry_iOS_SDK
let builder = FlurrySessionBuilder.init()
.withAppVersion("1.0")
.withLogLevel(FlurryLogLevelAll)
.withCrashReporting(true)
Flurry.startSession(apiKey: "YOUR_FLURRY_KEY", sessionBuilder: builder)
Flurry.log(eventName: "Purchase", parameters: [
"user_id": userId,
"value": String(price),
"currency": "USD",
])Heavy analytics SDKs do work at app launch — reading identifiers, initialising queues, network dispatch — that compounds visibly on lower-end devices. Respectlytics's SDK adds typically under 30ms to cold start, vs 100-300ms for Firebase Analytics's full initialisation chain.
☑Remove Flurry cleanly
-
1
Remove
pod 'Flurry-iOS-SDK/FlurrySDK'fromPodfile -
2
Remove
implementation 'com.flurry.android:analytics:...'frombuild.gradle -
3
Remove
react-native-flurry-analyticsfrompackage.jsonif used -
4
Remove
Flurry.builder().build(...)initialisation andFlurry.logEvent(...)call sites -
5
If you used Flurry's Configuration Provider for remote config, plan a separate migration (e.g., Firebase Remote Config, GrowthBook)
-
6
Delete the Flurry app entry once events stop flowing (the dashboard may already be sunset by the time you migrate)
⇋Flurry vs Respectlytics — faster cold start
| Flurry | Respectlytics | |
|---|---|---|
| Typical cold-start contribution (p50) | — see tool note above | < 30ms |
| Initialisation work on launch | Reads IDFA/AAID, opens SQLite, spins up threads | Allocates ring buffer (RAM-only) |
| Number of background threads spawned | — typically 2-4 | 1 |
| Synchronous I/O on init | — typical (SQLite open) | None |
❓Frequently asked questions
How do I measure cold start before / after?
iOS: Xcode Organizer's Launch Time metric (aggregate from real users) or Instruments → App Launch template (synthetic). Android: adb shell am start -W <package>/.<activity> or Play Console's Vitals → Startup time. Measure before removing the old SDK, after, and compare on the same device class.
Does Respectlytics block the main thread on init?
No. Respectlytics.configure(appKey:) is synchronous but does only in-memory work (allocates the ring buffer). The network flush runs on a background dispatch queue / coroutine.
What's typical magnitude of improvement?
On a mid-range Android device, removing Firebase Analytics + AppsFlyer typically saves 100-300ms off cold start, depending on Google Play Services init state. On iOS the delta is usually 50-150ms. Effect is more pronounced on cold-start (uncached) than warm-start launches.
Does cold-start improvement actually affect business metrics?
Yes — first-session abandonment correlates with launch latency in published benchmarks. A 100ms improvement on the slowest deciles of your device distribution can show a measurable first-day retention lift.