The fastest way for testing Dynamic Type while developing, and to quickly see how your app's UI flows, is by using the "option + cmd + plus/minus" to increase/decrease the text size in your simulator.
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Text Size is one of my favorite Control Centre controls. It lets you quickly change the Dynamic Type size, of the whole system. But also, you can now specify a different setting per app. Also, check out Dark Mode, Magnifier, Sound Recognition...
In addition to being able to test some accessibility options in the simulator using Environment Overrides. You can even preview some of these options before even running the app in the simulator with this Accessibility panel in Interface Builder.
If you need to send announcement notifications that can step into each other, they will by default, interrupt ongoing announcements. But you can pass attributed strings as parameters too, letting you specify announcements to be queued.
