For a number of reasons families might want to filter iMessage or other messaging apps like it. Circle currently doesn't manage Phone Calls or Texts, and you can read more about that in our article,
"Can Circle Manage Phone Calls or Texts?" In addition, Circle cannot manage iMessage in the vast majority of cases.
Why can't Circle manage iMessage?
Circle doesn't manage cellular capabilities like phone calls or SMS text messages. In addition, even with Circle Go it won't be able to manage iMessage. The iMessage system uses a number of fall backs to make sure that its messages get through. These delivery methods take a different route than the VPN that Circle Go creates and so cannot be stopped by Circle's filtering.
WiFi only devices
With the above said, there is one scenario where Circle will be able to filter iMessages. Here's the requirement for that.
1. iMessage must be used on a WiFi only device, without data or SMS ability.
2. The device is connected to your Circle managed network.
3. The device is under a Pause, BedTime, OffTime, or a Daily Time Limit has been reached.
4. The profile the device is assigned to does not have any platforms or categories set to "Unmanaged".