I can say my iPhone 6+ had issues with re-drawing apps if I left them and came back a little bit later (even as early as 2-3 minutes). I believe it was part of the saving battery thing where they restrict apps in the background except for certain processes -- Also I am sure the RAM didn't help.
That right there is my main holdback about this iPhone gen. It's likely they'll finally jump to 2gb this year but not assured. If they don't, it'll probably take it off my Fall upgrade list of contenders. One thing I admire about Apple is that they play by their own rules for specs rather than engaging in pointless spec wars. (QHD on a 5-6" screen? Seriously, what are you possibly going to do with that besides leading me to believe you have a virtual nose ring with the words 'sucker: salesmen please loop finger here' engraved on it?). But they shouldn't have applied that strategy to RAM this year.
Android OEM's are basically trapped into spec races because they have to one-up other android OEM's and they don't have the consumer clout Apple does to give them the ability to play leader.
Moto tried to downplay specs with the first X. Remember those debates? People were criticizing the specs, while Moto and their fans argued that user experience and optimization were more important. The kicker is that Moto was right... and also wrong. To the nerds and techie sites, the X was one of their darlings that year. But did it do well to the general public? Well...
Obviously there were other factors too but that doesn't change much. Moto, LG, HTC, Sony can't afford to release a flagship without THE most cutting specs like Apple can with their clout. Honestly I don't think even Samsung would get away with coming out next year with an S7 with toned down specs and saying "not necessary because we've optimized it so well" simply because they've already committed to the android spec war for so many years that if they tried to pull out they'd get torn to shreds in the media.