But - what if I have secured the iPad with a password.. Still these apps will prompt the message when iPad is in locked state.. Which looks like a bug for me..
Another possible bug.. when your iPad is locked and requires a password to unlock, still anyone can access your photos, just by clicking on the icon below..
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May be iPad has some options to handle these scenarios - even in that case this shouldn't be the default behavior when iPad is protected with a password.