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@Fireworks Yes, with iOS 14 or later, you can delete the built-in Photos app from your iPhone but it is not recommended

Not sure I trust the above AI response lol

When you take a photo it lands in Apple's photo app and then as far as I know Google Photos syncs it from there. That's how it works on my phone... I have under apple account, icloud, photos, 'sync this phone' off because I don't have room in iCloud for more photos. I have photos syncing to Google instead. My iphone syncs to google photos when I have the Google photos app open. I'm not a huge phone fan though so that's about the extent of what I know about it.

instead of deleting the app, I put unused apple apps in a folder on my last screen (i order apps by screen)

The trouble is the phone is really full cos all the photos are still sitting in the apple app

The photos have been downloaded  to Google but not deleted from the apple app so it keeps the phone really full

im worried if I delete them from the apple app they might delete from the Google site as well and be lost

If you're worried about losing things then it sounds like you don't have a backup strategy. I would look into making backups before you start trying to free up space.

I have both on my phone (but the larger storage). You have a few options. Cloud storage is cheap. iCloud is 200gb for $4.99NZ per month and can backup your whole phone which is very useful. You could use OneDrive for $3 (you likely dont need the more expensive options)  and 100gb which will also auto backup photos and if you have windows pc sync them to that as well. They will when backed up prompt you to delete off the phone. There are others like Google Drive (100gb and 200gb options at NZ $3.49 or $4.99 per month) as well but with all watch for the "upsell" the above plans do what you want with costing more than that.

I love backups and also for other reasons use all 3 as I fling data and copies all over :) I would go OneDrive if also use pc, GoogleDrive if just that and Apple ICloud if the phone backup as well is useful. As a big google user when I moved to the 16 promax from Android I was really worried but these days all Google just works (thanks EU). PS I may have 10998 photos and 341 videos in iCloud, Onedrive and Googledrive so yeah loss is not happening :D