Thresho v1 · California
Now recruiting California testers

Cool your home on timing, not AC.

Know whether to open, close, or wait, at a glance. No AC, no hardware, no account. We're looking for a small group of California iPhone owners to test it on real hot days.

Join the California beta Private TestFlight beta

California only · iPhone · free · no account required

CLOSE · rising OPEN · falling THRESHOLD

Thresho watches the forecast and tells you the exact moment to open or close your windows for free passive cooling.

Timing

Catch the Delta breeze

Thresho knows when the evening Delta breeze arrives and tells you the moment to open up, before your rooms heat back up.

Protect

Air-quality aware

When local air quality is poor, it holds the open-windows alert, so you are never invited to let bad air in.

Private

Yours alone

No account, no servers. It runs on your iPhone. Your location and your rules never leave your device.

Who it is for

Built for California iPhone owners who want a cooler home without running the AC. Nothing to buy, nothing to install in your house.

Step 1

Request an invite

Drop your email below. Tell us you're on an iPhone in California and we'll add you to the next batch.

Step 2

Get your TestFlight invite

We send an invite by email with a TestFlight link. You'll need Apple's free TestFlight app.

Step 3

Test it on hot days

Install Thresho and put it to work. Thresho isn't on the App Store yet, the beta runs until it is.

Request your beta invite

A small, private TestFlight group for California iPhone owners. Drop your email and we'll send your invite.

We'll only use your email to send your TestFlight invite. Invites arrive with a TestFlight link, you'll need Apple's free TestFlight app.

California · iPhone · free · no account