The iPhone 7 Plus was tested for its durability in real-life situations such as being submerged in water or having excess pressure applied to the screen.
In the US, smartphone insurer SquareTrade conducted a pressure and bend test on the iPhone 7 Plus and found that it only bent when 180 pounds of pressure - approximately 90 kg’s - were applied. However, we would still recommend you not sitting on your phone!
All in all, we’ll give the iPhone 7 Plus an 8/10 for durability.