Can the Android Wear and Tizen operating systems on smartwatches be challenged? French computer science student Florent Revest believes so.

Revest has developed AsteroidOS, a flavor of Linux for smartwatches, still in early beta. It has been tested on LG's smartwatches and a port is under way to Asus' Zenwatch 1.

AsteroidOS has basic smartwatch features like a calculator, calendar, stopwatch and heart-rate monitor features. Asteroid 1.0 could be ready for three to four smartwatches later this year, Revest said.

Like PCs and mobile devices, smartwatches usually come with an OS installed. Installing another OS like AsteroidOS could break a watch's warranty. Just as with mobile devices, installing a new OS on a smartwatch can be risky. Users have to be technically skilled or they could render devices nonfunctional.

For now, AsteroidOS is an enthusiast project, and a playground to explore applications that could be built for the emerging smartphone market.

It also is an early effort to develop an alternative OS for wearables, but its success remains an open question. Alternative OSes like Ubuntu, Firefox and Sailfish have been tried in smartphones, but failed to topple Android. Apple's devices are closely wrapped around the company's proprietary operating systems.

But Revest sees some advantages of having an alternative like AsteroidOS for smartwatches.

The OS gives users more control over smartwatch features. Users typically have limited control over data transmitted out of Android Wear smartwatches, and AsteroidOS will give fine-grained control over apps so there's more privacy for user data, Revest said.

AsteroidOS is also open-source, allowing developers to hack smartwatches to test new features and applications, Revest said.

"Someone created a stopwatch that is now included by default in Asteroid and there are other apps to write," Revest said.

As 3G/4G/LTE connectivity and more sensors are packed into smartwatches, more applications are being added. Android Wear smartwatches have time, notification, fitness tracking, location, cloud and health features.

Revest is looking for more programmers to write applications and testers to port the OS to various smartwatches. Making wearable applications is different from programming for PCs or mobile devices because of the different screen size and user interface, Revest said.

The user experience revolves around presenting relevant information like notifications at the right time. In Android Wear, "cards" are created to present important information while keeping resource usage minimal so the battery lasts longer.

The Linux-based AsteroidOS was built from scratch with the OpenEmbedded tool, with features drawn from other distributions. It has some drivers from Android, and middleware from the NemoMobile project.

The OS can be flashed directly to a smartwatch, or can be used as a secondary OS through an SD card.

Though AsteroidOS is only for smartwatches, a fair amount of features from the OS could be re-used on smartglasses and other wearables, Revest said.

Revest is a developer and student at French engineering university INSA Tolouse. He has developed gadgets like a Raspberry Pi-based autopilot quadcopter, and presented a paper on AsteroidOS at the recent FOSDEM conference in Brussels.