alt Hacker NewsAt some level, the machine code is the source code -- but decompiling AArch64 mobile apps into something like Java is common practice.
As GP alludes, you would be looking for a secondary pathway for message transmission. This would be difficult to hide in AArch64 code (from a skilled practitioner), and extra difficult in decompiled Java.
It would be "easy" enough, and an enormous prize, for anyone in the field.
I am familiar with disassembly and decompilation and what you just said is a huge handwave.
> a secondary pathway for message transmission
That's certainly the only way messages could be uploaded to Facebook!