For an excellent interview with the artist in Aperature, click HERE. (artmarketmonitor.com)
The areas for checking the leak are the window channels, the grooves which the glass slides in, are fully in place to the top of the window frame; The glass is sitting in the window channels squarely, adjustment can usually be made on the glass retainers behind the doors trim panel; The door aperture seal is correctly fitted and in good condition, the aperture seal is the usually rubber tube like affair fitted to the door aperature and which the door closes against. (mechanics.stackexchange.com)
Apple usually makes some kind of incremental upgrade to its cameras with new devices and while the 12 megapixel sensor did see an upgrade in aperature, from f / 2.2 to f / 1.8, performance seems about the same as the 6s Plus. (zdnet.com)