differences between smartphone processors?

i was looking at some android phones, one has a snapdragon 835 (or 800 series at least), another something like a 625, and another a 425, all in different price categories of course. all things being equal how will those different cpu's make an impact on the phone -- will the 835's speed be apparent in everyday things like launching an app, photo editing or web browsing? or is it mostly noticeable inthings like gaming? would a lower end 425 have a lot of lag? in other words when does a phone make use of a high end cpu's speed? thanks!