There is some discrete lag changing between apps, very rarely within them, with the BIG exception of the stock camera app. I have dealing with this issue since I bought my N5x and tried every suggested fix, none worked. It is impossible to use the stock camera app, it takes at least 5-7 secs to be ready for a picture, then after a couple of shots it freezes and can not take photos anymore, even closing the app, have to restart the device. I was not expecting this from a brand new nexus phone, very disappointed. I just came from a N5 and the experience was great for the last 2 years, and it still performs much better than the nexus 5x in almost every aspect. Undoubtedly, things have changed and the Google nexus team is delivering a below average quality hardware and/or software this time around. By the way, I have my phone unrooted and 100% stock just as it arrived with all the updates. So no excuses here and no fix from Google till now. It is like going back to the begginings of 2010 first smartphones era. Found this completely unacceptable and asked for a refund.