On the Migros websites, I unfortunately notice time and again that the recognition of mobile devices and features is done in a careless way. For example, the Edge browser on Win10 Mobile shows that WebGL is not supported by the browser, which is not true. On the mobile site for digital coupons, you are redirected to the Google Play Store, which is also completely wrong.
If you don't want to support all operating systems, that's your decision, but please use feature detection and implement redirects properly.