For those of us on older phones that don't have the capability to receive these alerts directly, there are apps for both iPhone and Android that connect directly to the Alert Service to provide the National Alerts (and actually some more useful info as well.)
These apps will also work for those who have set their phones to 3G only or WiFi only, where even compatible phones wouldn't receive the alerts.
Here's a comprehensive list of phones that aren't compatible (phones newer than the date of the article should be compatible with the Alert system).
I will get this test while in Ottawa at a conference should be interesting to see how many phones go off in the conference room.
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