How do you reduce the memory footprint and stay clear of jetsam?
Essence
iOS has no swap to disk: when memory runs short, the system first compresses and drops clean pages, then terminates processes (jetsam). The decision is based on the footprint — the process's dirty plus compressed memory. Every app has its own limit, and in the background the app holding a lot gets terminated first. To the user it looks like "the app restarted", and there's no regular crash log.
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