I would add that unless you have some imperative reasons to use specific device checking, you should try to only rely on screen width.
People and apps on mobile devices frequently change their user agent, so if you rely on this you are never sure if your visitors will see the proper content.
Screen size allows you to be sure that the content will look good based on the available screen real estate of the device.
Xtreme has device / OS / size classes you can use (see below) and you can of course use @media rules and all their options.
Below is an extract of the help file on this
Weaver Xtreme Helper Classes
Weaver Xtreme provides quite a few helper classes that can be used to help style your content. You can used these in the any of the PlusHere’s a short summary.
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- .show-desktop – show on devices; add these classes to show or hide by device
.show-mobile
.show-smalltablet
.show-phone - .hide-desktop – hide on devices
.hide-mobile
.hide-smalltablet
.hide-phone - .is-desktop – prefix selectors to make rules apply on specific devices
.is-mobile (either small-tablet or phone)
.is-smalltablet – note: many phones will be considered smalltablet when in landscape view
.is-phone – usually when in portrait mode only
.is-ios – an iOS device: iPhone, iPod, iPad
.is-ipad – an iPad
.is-ipod – an iPod
.is-iphone – an iPhone
.is-android – any Android device
.is-windows – any Windows OS
.is-macos – any Mac OS