Reader Martin Roth runs a YouTube channel, in part dedicated to comparing camera phones - and he's now put up videos on the Nokia 808 PureView versus the Apple iPhone 8 Plus. Worth a watch as he goes into some detail, comparing shots like for like.
There's also a chat in German, but to get English subtitles, maximise the window and then dive into the YouTube player settings - set the 'subtitles' to be 'Auto translate' and then 'English' (or whatever):
Comments? The subtitle system doesn't work perfectly, but you'll get the gist!!