iOS replications background behaviour

Why are continuous replications automatically suspended when the app is put into the background?

And would anything adverse happen if they were resumed (and kept resumed) when the app was placed into the background?

They’re only suspended if they’re idle, IIRC.

An iOS app can only keep running in the background if it requests a background task, and the OS only gives that task a limited amount of time (something like 30sec) to run. After that the app simply stops getting CPU time, so it freezes until resumed.

The OS also closes sockets when an app is suspended/frozen, so the replicator should cleanly shut down its sockets before that happens, to conserve server resources.

In general the expectation on iOS is that an app in the background isn’t consuming any device resources unless the user asked it to. So if the replicator is actively pushing/pulling stuff, it’ll try to complete that. If it’s not, it just pauses.