It's true Signal uses APN to wake up the receiver's phone, but it does not pass any message content through Apple's servers. It could not, because Signal itself is unable to read the encrypted message content. The definitive proof of this is in the Signal source code. This is for iPhone, similar implementation for Android in FcmSender.java
https://github.com/signalapp/Signal-Server/blob/main/service/src/main/java/org/whispersystems/textsecuregcm/push/APNSender.java
Adam Lein (npub1fd4…rwtl) Per Axbom (npub1aer…7756)
Osma A 🇫🇮🇺🇦
npub1h4…9akl9
2026-04-10 04:18:23 UTC
in reply to nevent1q…nc5p
Author Public Key
npub1h44tyyg9g8hh878k64vnfufymyhqxud00ftddmc5zudfx4d646aqu9akl9Seen on
wss://relay.momostr.pinkPublished at
2026-04-10 04:18:23 UTCEvent JSON
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