I. Data
The image generation process is done locally. Thus, we cannot read the text phrase you entered, or the image you generated.
This app stores the content you entered (generated images, prompts) into your iCloud private storage, within your own Apple ID. The developer cannot access this information.
Only devices signed into your Apple ID has access to these information. Apple Inc. manages the data within iCloud.
You need to refer to iCloud to understand how they manage these data.
To turn off iCloud syncing, go to system settings, open iCloud, and then turn off the toggle for this application.
II. Crash Logs
When the program crashes, a crash log will be sent to Apple Inc. to help us improve the application. The crash log will not contain your personal information.