Hi there! I understand the Ski Tracks app on your iPhone starts up fine but crashes when you select a category like Skiing or Snowboarding. Just to clarify, which iOS version is your iPhone currently running? Also, do you recall if you recently updated either the iOS or the Ski Tracks app itself before the crashes started?

In the meantime, here are some initial steps you can try that often resolve these types of crashes:

1. Update the App: Make sure you have the latest Ski Tracks version installed. There was a known issue with some versions crashing on newer iOS versions (iOS 17.4 specifically), resolved in Ski Tracks version 3.0.3 build 203 or later. Updating the app may help fix this1.

2. Restart Your iPhone: Shut down your iPhone completely and then power it back on. This can clear temporary glitches.

3. Reinstall the App: Delete the Ski Tracks app from your iPhone, then reinstall it from the App Store. This can help if the app files got corrupted3.

4. Clear App Cache or Data: While iOS doesn’t offer direct cache clearing like Android, reinstalling achieves a similar effect.

5. Check for iOS Updates: Make sure your iPhone is updated to the latest stable iOS version available for your device.

Could you try these steps and let me know how it goes? If the problem persists, I can guide you through more advanced troubleshooting.