Hi there! I understand your Tile Family app keeps shutting off on your iPhone, even after restarting your phone and reinstalling the app with sync enabled. Let's work through this together to resolve it.

Since you've already restarted your iPhone and reinstalled the app, here’s what I recommend next, step-by-step:

1. Force Close the App Completely
- On your iPhone, swipe up from the bottom (or double-click the Home button if your model has one) to open the app switcher.
- Find the Tile Family app and swipe it away to close it fully.
- Then, open the app again and see if it runs smoothly.

2. Check for App and iOS Updates
- Go to the App Store and check if there is an update available for Tile Family. Installing the latest version can often fix stability issues.
- Also, navigate to Settings > General > Software Update to ensure your iPhone is running the latest iOS version (your current is 18.6.2, which is recent but good to double-check for any minor patches).

3. Verify Internet Connection
- Since Tile Family relies on syncing data, a stable internet connection is crucial.
- Try switching between Wi-Fi and cellular data to see if one works better.
- You can also try resetting your network settings if connection issues persist: Settings > General > Transfer or Reset iPhone > Reset > Reset Network Settings (note this will erase saved Wi-Fi passwords).

4. Check Storage and Background Activity
- Ensure your iPhone has enough free storage, as low space can cause apps to crash. Check in Settings > General > iPhone Storage.
- Close other apps running in the background that could be consuming resources.

5. Disable Background App Refresh and Re-enable
- Go to Settings > General > Background App Refresh, turn it off for Tile Family, then restart the phone and turn it back on.

6. Advanced Step: If the app still crashes
- Try logging out of your Tile Family account in the app (if possible), then log back in after restarting the app.
- If this doesn’t help, saving your progress and data externally would be wise, then uninstall and reinstall again fresh.

If you want, I can walk you through these steps in detail. Also, could you tell me if the crash happens immediately at launch or after some time or activity inside the app? That will help me narrow down the cause.

Are you satisfied with this approach so far? Let me know, and we’ll get your Tile Family app running smoothly!