Not on the phone. The Light Phone III texts over SMS, and Light’s support page tells people who switch to turn iMessage off. With Decaf, iMessage stays on at home, on your Mac, and the texts that matter reach the Light Phone III as SMS, with a way to reply.
The Light Phone III has no iMessage and no RCS. Texts, pictures and group texts go over SMS and MMS, so a group chat with iPhone friends arrives as a plain group text, without reactions or typing dots (TechCrunch, May 2026; Light’s FAQ).
Light’s support article Disabling iMessage/RCS says to turn iMessage off and deregister your number before you move it. After that, iPhones that text you fall back to SMS, and the group chats you were in go on without you.
A community tool, bubble-light, puts an iMessage client on the III using Light’s developer kit and a Mac of your own running BlueBubbles. Light doesn’t endorse it, and it can’t send photos or notify you while it is closed.
The III is $899, on pre-order for late December 2026 (Light).
Decaf is a calm iMessage Mac app that relays time-sensitive and important texts to a second phone. Your iPhone keeps your main number and stays home, plugged in. The Light Phone III gets a number of its own. Decaf, on your Mac, texts the Light Phone III when something can’t wait; the rest waits for when you sit down.
You answer in the same thread. Before a reply is relayed, Decaf asks for confirmation, and it goes out from your main number, as if you had typed it on your Mac. Your group chats stay where they are.
Decaf
Decaf works while the Mac is awake and online. You will be slower to reply than you were from an iPhone.
Decaf’s setup assumes your main number stays in your iPhone. Four things to decide before you call your carrier.
Already moved your main number to the Light Phone III? Then it isn’t in an iPhone any more, and Decaf has nothing to relay from.
Free 14-day trial. Then a $20 one-time purchase.
Join the waitlistSetting up takes about 10 minutes with both phones handy. The setup guide has every step.