Re: "network lag"
Not sure why you were downvoted, as that seems like one perfectly reasonable explanation.
I also suspect a lot (most?) of it has to do with the VM bloat of
Java Dalvik/ART, and the fact that Android in general is a convoluted mess under the hood. That wouldn't explain why iOS has roughly the same performance issues, though, since AFAIK it's fully native. I presume Windows mobile is using some .Net/CLI garbage.
Or maybe it's that relic known as Secure Digital storage, or the pitiful speed of ARM main buses, or some other bottleneck that isn't obvious.
Whatever it is, it's truly shocking that the technology is moving so slowly that it's still outperformed by thirty year-old systems from the 16-bit era.