Yet display unit iPhones never perform badly.
As such, we have our answer.
No........
For example, a Galaxy S8 is LOADED with demo software that shows off all the cool features, etc; but completely inhibits you from doing anything normal for more than a few seconds. Then it switches back to demo.
Thus, you are making a statement of fact, without actually knowing what you are talking about.
All phones lag, even iPhone/iPads. I should know, I have owned every major iPhone/iPad/Pixel/Nexus/Galaxy/and even a few recent flagship Lgs & HTCs. They hide their lag differently, behind how the mutlitasking operates. This comes down to application storage, animations, etc.
The iPhone does the best at hiding lag, while the Pixel does the best with mutlitasking. Don't post a unrealistic youtube video of a speed-test, this is based off my personal long-term experience. Pure Android can go toe to toe with iOS, and I wouldn't make a bet. They are both going to succeed, and fail, in their own way.
I currently use the Galaxy S8+. In the past, Samsung was the worst about UI lag, and I still wouldn't put it on the level of the Pixel/iOS; but that is only in a side by side, useless comparison. The phone is super fast, super reliable, and that goes along with the gorgeous design, great camera, features, etc. The touchwiz launcher is the only play that lag is ever apparent, and Samsung is finally acknowledging that. An update was just released last week or so that directly addressed some of this lag. Personally, I wouldn't know, I always end up using Action Launcher on my Android phones, which eliminates any launcher/homescreen inconsistencies.
iPhone and Android are largely similar, when it comes to fixing "lag". If/when it appears, restart the phone. If this doesn't fix it, and you don't have a poorly coded rogue app (unique to android, increasingly rare, unless you go looking for crap apps, but this freedom allots many of android unique features/advantages over iOS), do a factory reset. Modern Pixel/Galaxies (I haven't recently tried this on another brand) backup and restore features are on parity with iOS. If this doesn't fix it, you have a faulty phone.
Beyond major hang-ups, which can be addressed as indicated above, this "lag" that people harp on here is largely miniscule and pseudo. If you get upset/worked up over the occasional hang, take a deep breathe and examine your expectations. I am not going to judge you and tell you to get a life, because tech is becoming increasingly integrated into how we live, but do keep a perspective. Maybe your Galaxy S8 (mine doesn't, but maybe yours does) occasionally hangs for a millisecond when you jump into a Samsung brand app (which you don't have to use); at the same time my Siri on my iPhone has failed for the 1000s time trying to give me simple directions. Every phone has its advantage and disadvantage.
The same can be said for Windows 10/macOS. I used to be a dire-hard macOS person, until the recent MBPtb, in which I purchased one, became increasingly frustrated, and moved on the Widows 10 (happy here). But, again, advantages and disadvantages.
Man, I always end up writing a book on here. Tl;dr? Enjoy your phone, and pet your dog today.....
***I didn't really read previous post, so keep that in mind. Also, the new iPad Pros, in my mind, are exempt from the "every device lags" argument. I have one, and it is the most fluid device I have used. While I can't say the same for other Apple products at the moment, the iPad Pro line is by far and away the best devices in their class; it is not even close. But, as we see with apps such as affinity photo, even these devices will be tax/lag as developers eventually harness their power (but this will largely be on cutting edge, professional apps, due to developers desire to appeal to a wide range of devices).***
