There are lots of USCIS case trackers in the market. Some of them has push notifications when status changes. But why is Green2US the fastest USCIS case tracker?
Just Because of Refresh restriction
All phone apps can’t refresh the case freely when they are not on the screen. Especially, iPhone apps have no control on when to refresh their data, which means they can refresh your case and notify you 15 minutes to hours later.
On the other hand, Green2US is a service running on the cloud. It can refresh your case every 15 minutes when you choose Relax plan. Green2US can even support refreshing every 5 if any customer needs it.