If you've had an iPhone for a very long time, there is a pretty decent chance that you're also still on AT&T — and you get battered with spam phone calls. AT&T has an app to help deal with that, and AppleInsider has taken a look at it.

The app, unsurprisingly called "AT&T Call Protect" is free and available from the iOS App Store. It purports to allow users to manage incoming calls granting "more control over nuisance calls."

There are a couple of caveats — it only works in AT&T's HD Voice coverage areas, won't block "unknown" callers, and will only block a user-selected unwanted call for 30 days at a time. If all those conditions are met, if an incoming caller is on AT&T's block list, its labeled as a "Suspected Spam" both in the phone log, and in the app.

Setup is reasonably simple. After the app is installed, the app asks for a phone number. AT&T sends a PIN through a text message, and users enter the code in the app.

Across a few different devices in three geographical areas, the app alerted us that "We Hit a Snag" and failed to continue to activate — which seems to have been a wide-spread problem when we initially installed the app. Ultimately, patience was all that was required, here — in every case we tried to activate the app later in non-peak network times, and it completed the registration without further incident.

The app's settings are straight-forward. There is little that can be configured in the app, with simple toggle switches to activate or disable Automatic Fraud Blocking and Blocked Call Notifications.

The numbers tested with the app have been in continuous service since the iPhone 3g — as such, the number has been spread far and wide receiving about 7 spam calls during a weekday. The federal "no call" list helps some from the peak of almost 20 per day from seven years ago, but isn't absolute.

In our test cases, the app notified us all but one spam call, and didn't appear to block any calls we actually wanted, such as the local county's central phone system, or call center call-backs from companies like Verizon or CVS.