they know he used Signal. Not sure you can know what he used it for. https://www.wikihow.com/Know-if-a-Contact-Is-Using-Signal https://www.wikihow.com/Know-if-a

they know he used Signal. Not sure you can know what he used it for. https://www.wikihow.com/Know-if-a-Contact-Is-Using-Signal https://www.wikihow.com/Know-if-a-Contact-Is-Using-Signal also there are some conspiracy theories that Signal is actually CIA's puppet: https://kitklarenberg.substack.com/p/signal-facing-collapse-after-cia https://kitklarenberg.substack.com/p/signal-facing-collapse-...