Samsung Galaxy Note 4 release date; 5.7 inch 4k flexible display and slimmer body?

Will the Samsung Galaxy Note 4 come with more metal, more display and, well, more everything than its little brother, the Note 3?

The Samsung Galaxy Note 3 is a pretty solid device but one concept image is reimagining its successor to have some of the weight shaved off and a much more streamlined device.

Simion Popa's concept image on Concept Phones pulls together the rumored elements like a quad HD AMOLED display, as well as a touched up user interface and Bang&Olufsen speakers - wouldn't that be nice! 

Simion also imagines more metal and a much more rectangular device to replace the more rounded Note 3.  That would bring the design much more into line with HTC. 

The image suggests the device will be 5.7 inches and come with a 21.5MP camera and 8MP front camera.  

Other rumors from the Note 4 rumor mill point to an Android 4.5 Lollypop operating system powered by a 64-bit processor.  As the Samsung Galaxy S5 is already water and dust resistant, it's unlikely the Note 4 would neglect this feature.

Tongues have been wagging in the last week over whether the Galaxy Note 4 will be one of the first devices to come with the new Qualcomm Snapdragon 810 chipset, rather than Samsung's octa-core processors. 

And while it sounds staggering to have a 4k flexible display, that is indeed the latest speculation.  

So when can we expect this spec-packed device to land in our hands?  Some time between 4 and 10 September seems probable, when the IFA trade fair takes place.