Nest is about to give its Learning Thermostat and Protect smoke detector a big potential boost in functionality. The Google-owned company has just launched its developer program and API, which will let anyone write software that can integrate with Nest's products. The initiative was first announced last September, but Nest's developer portal is now open after a year of work to anyone with a free Nest account.

Greg Hu, senior product manager at Nest, said the program's goal was let anyone with a connected platform talk to Nest's products. "It could be software, it could be hardware, it could be a service," Hu says. "You just need a connected platform and that's it." To show off what its new platform can do, Hu and the Nest team have lined up a variety of initial partners — from massive companies like Mercedes-Benz and Whirlpool to smaller players like Jawbone and IFTTT.

"You just need a connected platform, and that's it."

Probably the headlining feature Nest is showcasing comes as a result of its Mercedes partnership: ETA. "Basically, it's estimated time of arrival, which tells Nest when a person is actually going to be home so that we can heat or cool accordingly," says Hu. The partnership with Mercedes was first announced back at CES earlier this year, but anyone will be able to use the ETA feature, allowing users to send a signal to their device at home and have the Nest kick on so the house is comfortable when you arrive. ETA sounds like a clear response to Honeywell's recently-announced Lyric thermostat, which uses geofencing to activate its heating and cooling system when you're on your way home.

In addition to having access to Nest thermostat controls, they also have access to the Protect's smoke and CO2 event alerts, which opens up new ways for users to get notified or alerted to potential hazards. Lifx, an Australian company that makes Wi-Fi LED lightbulbs, came up with a way to turn all the lights in a house red when the Nest Protect detects smoke. The red color makes it easier to see through smoke, and the lights pulse as well — providing visual cues to a hearing-impaired person who might otherwise miss an audible alert.

The endlessly customizable service IFTTT is another API partner, and the flexibility the service offers means developers will likely come up with a wide variety of potential actions. "One example would be if Nest Protect detects smoke, you can get a text messages sent to your neighbors," Hu says. "That's surprisingly simple and powerful at the same time — you can extend what is a typical kind of personal safety notification to people who can help you in those situations."

Any company — even Apple — is welcome to use the Nest API

Developer creations will have to make it past one stage of review, once they hit 1,000 users. "We're checking it, testing it twice, and ensuring that it's a really good customer experience," says Hu. "We have developer guidelines, UI guidelines, and everything's really clear on our developer portal." When asked if Nest would accept software written by Apple, Hu reiterates that "any company is welcome to join the program"  as long as a developer follows Nest's "fairly straightforward guidelines."

The timing of the launch makes a lot of sense for Nest — Google I/O kicks off on June 25th, and the company will be there to hold a session with co-founder Matt Rodgers to get developers on board with its new platform. While the company only has two products available and appears to be content releasing things at a measured pace, the ability to extend the features of those devices automatically strengthens Nest's position in the smart home. While it doesn't appear that any one company will crack that code in the near future, if Nest's new API means it can gain big traction with developers (like Apple did with the App Store back in 2008), it could have a big leg up on the competition going forward.