Finnish mobile startup Jolla has big plans for its nascent Sailfish mobile OS to emerge as a genuine rival to the likes of Android and iOS, and now it’s taken a massive step in achieving those goals with the announcement of compatibility with Android’s software, apps and even its hardware ecosystem.

This is a huge deal for Sailfish OS, which will now be able to run native Android apps as well as those built to run on Sailfish alone, said the company on Monday. More importantly though is the hardware compatibility – which means that people will be able to install the Sailfish OS on existing devices, so long as these are Android compatible. To date, Sailfish OS has only been seen on a few homegrown handsets built by Jolla – all of which have sold out even though they’re not scheduled to ship until December. However, with the hardware compatibility it means that Sailfish OS will now be able to run on a range of the most popular Android smartphones and tablets, such as the Galaxy S4, Sony Xperia, Galaxy Tab and more.

“Vendors interested to utilize Sailfish OS are now able to develop phones and tablets based on many different chipset and hardware configurations. This new level of compatibility will enable device vendors who use Sailfish OS to fully utilize the existing Android hardware ecosystem.”

Jolla hasn’t said how it managed to achieve hardware compatibility with Android devices, but given that other Linux-based operating systems like Ubuntu Phone, Tizen and Firefox OS have achieved broad hardware compatibility by building themselves around the Android device driver model, this isn’t entirely surprising.

It’s also unclear how Jolla has managed to make Android apps compatible. On Twitter, the company stated that the Android layer runs within its own sandbox, but admitted that the experience might not be quite up to scratch:

.@NMShenoy Definitely, native apps are the only way to utilize the Sailfish UI to the full.

— Jolla (@JollaHQ) September 16, 2013

Even so, the Android apps will be there, and most likely in their thousands too:

“Jolla will cooperate with leading global app stores to ensure users can seamlessly download Android apps just as they would do on any Android device,” the company continued in its press release.

Jolla hasn’t said which Android app stores it’ll be working with to provide apps for Sailfish, but (not surprisingly) it did rule out any cooperation with Google Play, most likely because of the strict requirements that Google places on device makers before they can distribute its Play store application.

The company said that it would provide more details of its hardware and software compatibility soon, “as it works on the solution”.

In the meantime, Jolla is also working to bring a second batch of homegrown Sailfish OS phones to the market, which will only be made available to consumers in Finland owing to strong demand in the country. Sailfish OS phones will be made available in other countries at a later date, the company said.