Hi there! I understand that the Zen Color app keeps stopping on your iPhone, and that can be frustrating. Let's work through this together to find a solution.

Here are some steps you can try to resolve the issue:

1. Update the App: Make sure you have the latest version of Zen Color installed. Open the App Store, search for "Zen Color," and see if there's an update available. Updating can fix bugs that might be causing crashes.

2. Clear App Cache: iPhones don’t have a direct way to clear app cache like some Android devices, but you can try deleting the app and reinstalling it. This process can help remove any corrupted data that might be causing the issue. Just keep in mind that uninstalling the app may lead to losing any unsaved progress.

3. Restart Your iPhone: You mentioned that you have to restart your phone; however, let's ensure it's done correctly. Hold down the power button and either volume button until you see the slider to power off. Once it's turned off, wait about 30 seconds, then power it back on again.

4. Check for iOS Updates: Make sure your iPhone's operating system is up to date. Go to Settings > General > Software Update, and install any available updates.

5. Free Up Space: If your iPhone is running low on storage, it may cause apps to crash. Go to Settings > General > iPhone Storage to check your available space and delete apps or files you no longer need.

6. Reset All Settings: If the issue persists, you could try resetting all settings on your iPhone. Go to Settings > General > Reset > Reset All Settings. This won't delete your apps or data, but you will need to re-enter Wi-Fi passwords and adjust some settings afterward.

If you try all these steps and the app is still crashing, there might be more complex factors at play, and I would recommend reaching out to Zen Color support directly at [email protected] for further assistance.

Are you satisfied with the solution I provided? If the problem continues, we can explore more options together!