Two things that seem natural fits to me for the 2016 iPhone: both sizes get a 3x retina display, and all vibrating alerts are replaced by a more powerful, nuanced taptic engine. I've not seen this rumored anywhere, but the parts that have leaked don't preclude the possibility. Both seem like something Apple would do to make this update feel less lackluster, and both seem pretty easy to keep secret until the announcement. What do you think?