The English version isn't limited to a simple list of functions but describes what secret chats do using the title ("Secret Chats", "Chat segrete" in italian) as an implied subject.

If the other translation proposal isn't convincing I recommend a small change. The English version specifies "Leave no trace on OUR server", then in Italian (taking up the official translation) "Nessuna traccia sui NOSTRI server".

"Nei" is more accurate because data is saved "inside" the servers.