Why do you want to know that? apps should behave the same way on real devices and simulators, so trying to know if it’s a simulator it’s usually not a good thing to do.
It’s not possible to know from the front end, so you can’t know by just using Ionic.
If you are using Capacitor, you can use
@capacitor/device plugin, the
getInfo() method returns a
isVirtual property, which works well for iOS simulators, but not so good for android emulators.