It shows you the interviews currently open at one of the 119 Global Entry enrollment centers, and updates as that changes. Everything already on offer when you start is your starting point. From then on, anything that appears is called out on the page, with a sound if you turn it on.
You are not scanning anything yourself. TTPRadar already watches these centers continuously for its text-alert customers, and browser alerts read the same availability. Ten people watching the same center is still one check, not ten.
What it cannot do
It only runs while this page is open and awake. Close the tab, quit the browser, lock your phone or leave the page in the background for long enough and your device stops it. An interview that opens overnight is one you will find in the morning, if it is still there.
That is the difference the paid alerts buy: text alerts keep running on our servers with nothing open on your side, watch up to three centers at once, only tell you about the dates you asked for, and reach you wherever your phone is.
When you get an alert
Book it yourself on the official Trusted Traveler Programs site. Cancellation slots can go in minutes, so keep your login to hand.
TTPRADAR