Preventing photos from iOS apps saving to camera roll

but that prevents the app from being able to access the photos.  What I am trying to do is stop photos going from the app to the camera roll but I dont want to prevent the ability for the app to take photos from the camera roll.....if that makes sense?

By switching off those things shown under privacy, what is it actually doing, preventing total access or just the meta data i.e. data about where the photo was taken etc?

yes but for whatsapp, I have the "Save incoming media" slider switched off but it is still saving the media......

That is a pity.

So looking at your question and answering it as best as possible.

If the app has a possibility to use media such as images and data, then it depends on the developer where he saves it. He could save it where you have access or he could save it in the apps own file system.  If they are nice they might give you the option to not save it.  In the case of Whats app if the image is not saved then at some stage when you scroll through your conversations you will have blanks where an image once was.

If the developer does not give you some option to stop saving images then you can only globally stop it in the settings.  My guess however is that whats app will simply save them elsewhere if you do not give it access to the photo roll.  I am guessing this because otherwise your chats would not work properly.

Justin I'm no sure I understood your last comment, pls explain.

Thanks, I should have searched the FAQ for Evernote on this and have found a solution which has stopped it.  Also whatsapp is not saving to my camera roll as I thought.