Even if you install Signal, you'll still have iMessage installed and processing messages sent to your apple ID. iMessage on iOS is part of the OS, and does som

Even if you install Signal, you'll still have iMessage installed and processing messages sent to your apple ID. iMessage on iOS is part of the OS, and does some message handling in kernelspace. Yes, it has blastdoor, but even since blastdoor sandboxing has been introduced, there have been multiple iMessage CVEs which lead to a full device compromise. See this project zero post for more about iMessage [0]. What I'm trying to say here, is that on an iPhone, no matter what messenger you use, some iMessage exploits can pwn that messenger anyway since iMessage cannot be disabled, and has privileged OS level access. On the other hand, android does have "google messenger" or whatever the OEM installed, and it may not be uninstallable, but it's sandboxed away from the OS in the same way every other app is. There have been exploits based on kernel-space processing of media attachments on android too, but those actually did depend on the app being used, so if you switched SMS apps to one which rejected such an attachment, or otherwise processed it differently, you actually could be secure. Said another way, on android you actually can turn off the default messenger and use signal for SMS. On iOS, that's not so realistic. [0]: https://googleprojectzero.blogspot.com/2021/01/a-look-at-imessage-in-ios-14.html https://googleprojectzero.blogspot.com/2021/01/a-look-at-ime...