"Is there an iCloud app on iPhone?: My iPhone has iCloud Photos and also has iCloud backup but somehow I see no iCloud app icon anywhere on the iPhone except in settings/iCloud. So shouldn't the iPhone's desktop show an iCloud app?"
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iCloud App:
No. No such app exists. But, you'll find photos directly in in the Photos app, or in the Drive app. So, enable Photos and Drive in iCloud Settings.
Enable Photos and Files in iCloud:
On the iPhone:
- Go to: Settings
- Tap: Your Name (Top Item)
- Tap: iCloud
- Tap: "See All >" in Saved to iCloud
- Tap: iCloud Photos
- Toggle On: Sync this iPhone
- Tap: < iCloud (top-right)
- Tap: iCloud Drive (top-right corner)
- Toggle On: Sync this iPhone