**What is the APSD?** The APSD is *the Apple Push notification Service Daemon.* **What is the IMAgent?** [(1)](https://apple.stackexchange.com/questions/86814/firewall-settings-with-imagent) [(2)](https://shindan.io/kb/ios/processes/daemons/imagent/) The IMAgent is *a process that listens for FaceTime or iMessage invitations even when FaceTime isn't running.* **What is the IMDPersistenceAgent?** The IMDPersistence agent is ...