Apple’s emergency SOS feature has proven useful for a fair number of people whose cars break down (or tumble down) in areas with no signal. Soon you’ll be able to use iMessage and SMS as well — though it’s not clear what the limitations on the service may be.

Announced at Apple’s WWDC 2024 keynote on Monday, “Messages via Satellite” works much like the SOS feature does. When you have no signal — otherwise the phone will use that — you’ll be given the option to find a satellite to relay the data. You’ll have to keep the phone pointed in the right direction while you do it, as an overlay above your messages will remind you.

Apple was sparing of details during its presentation, and didn’t mention any limitations or charges. Until the full announcement comes out we can’t be sure, but it appears to be free and unrestricted.

For sending text, that is. Images use much more data and can’t be sent, as before, but if you’re connecting with your correspondent via iMessage, you will have the benefit of end-to-end encryption. This does add data overhead so it wasn’t clear whether the very bandwidth-limited satellite connection would be allowed to use it, but Apple made it clear that privacy measures will stay intact.

That won’t be the case if you’re using SMS, ordinary texting in green bubble form; encryption has never worked there, so just keep it in mind that you’re talking on an open line shooting out to space and back.

Apple did not say when the new feature will be available or whether it’s restricted to certain phones or plans. We’ll update this post when we know more.