What resolutions should be chosen for transition borders in responsive layout?

Question

Layout

At first I got used to botstrap, where devices were divided into mobile (less than 768px), tablets (from 768px to 992px), computers (from 992px to 1200px) and large monitors (from 1200px).
Since the advent of such a division, a bunch of devices have appeared on screens, and phones already fall under resolutions from 768px to 992px, and planets occupy most of the resolutions from 992px to 1200px.
What resolutions should be chosen for transition borders in responsive layout now in order to cover the most used devices (phones, tablets, PCs)? Have these transition boundaries changed, and are they currently enough of this number of transitions for those involved in adaptive design/layout?
Advise or tell me which 3-5 borders (screen width sizes) to choose for an adaptive site.

Answer 1

Firefox -> Open Menu -> Development -> Responsive Design.
Voila, there are the most popular options + the ability to put the smartphone on its side.
Borders: smartphone (iphone 4,5, etc.) -> shovel (ipone 6 plus, galaxy note) -> mini tablet (ipad mini, google nexus 7) -> big tablet (ipad) -> desktop
+ much more I recommend this article: habrahabr.ru/post/237931
+ in general, the content should be rubbery to some extent, say from 320 to 370 just rubber, but only 370+ transition.

Answer 2

In principle, the dimensions in Bootstrap are quite consistent with reality, since new devices increase the number of physical pixels, not logical ones. Therefore, whatever the screen, even if it is 4-5k, but with a phone size of 5 "it needs to give a phone page of 360-480px.