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27 August 2025

Migrating to the Watch Face Format - Amoledwatchfaces’ journey


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Posted by Garan Jenkin – Developer Relations Engineer
This post is part of Wear OS Spotlight Week. Today, we’re exploring how Amoledwatchfaces successfully migrated to Watch Face Format, improving customization, extending battery life, and increasing development speed.

Amoledwatchfaces is a leading creator of watch faces for Wear OS using the Watch Face Format (WFF), known for a distinctive information-rich and crisp style. Now well-established on the platform with over 190 watch faces, we talked to Tomáš Marcinčin, owner of Amoledwatchfaces about their successful migration using the format, and the benefits he’s seen in development velocity and performance as a result.

Creating high-quality watch faces without complex code

In previous years, developing watch faces “took a lot of time,” says Tomáš Marcinčin, owner of Amoledwatchfaces. The AndroidX libraries allowed developers to create watch faces, but Tomáš, like others, was left looking for an “easier way to create watch faces,” and crucially one that shifted the focus from coding and onto design.

“My main motivation was to bring users watch faces that are of the same quality as those that are pre-installed. Users were looking for designs that were not too complicated, yet customizable and looked as if they had been designed for that watch.”

Expressing interest in a customized experience

Like many creators, Tomáš started using Watch Face Studio, Samsung’s watch face creation tool, giving designers and developers an easy way to build watch faces for Wear OS quickly.

While successful, as a developer, he found himself wanting more control, and a solution that was somewhere in between Watch Face Studio and full code - this led him to working directly with the format.

Stealth and Apex 2.0 watch faces from Amoledwatchfaces
Stealth and Apex 2.0 watch faces from Amoledwatchfaces

Migrating to Watch Face Format

Amoledwatchfaces already had a significant back catalog of watch faces, and took on the dual task of both converting all his existing watch faces and producing new ones directly in the format. “I wanted to have every old and new watch face design in WFF.” This would ensure that all Amoledwatchfaces’ watch faces would be available to current and future users.

Tomáš started working directly in Android Studio, gradually refining his build process. Android Studio has recently added support for syntax validation - a feature Tomáš fed directly into and helped test as an early adopter.

Once up and running, Tomáš found that some of the most time-consuming tasks of AndroidX were extremely simple in the format. Notably, adding the level of user customization he - and users - wanted “is very easy.

As an example, some of Amoledwatchfaces’ users wanted different Always-On Display (AOD) styles - some preferred a dimmed view of the active state, whereas others wanted only the digital clock. Using Variant, and configuration options such as ListConfiguration and BooleanConfiguration, it was straightforward for Tomáš to give users the ability to customize their watch face - something which would have required a significant investment using legacy libraries.

<Variant mode="AMBIENT" target="alpha" value="[CONFIGURATION.aod] == 0
    ? 255 : [CONFIGURATION.aod] == 1 ? 165 : 0" />
Customization of the ambient behavior: Using a ListConfiguration to select between full opacity (255), a middle ground (165) or invisible (0), for a particular component

Overcoming Watch Faces quality and versioning challenges

To shorten the debug cycle and minimize errors, Tomáš uses the WFF validator and memory footprint tools in his Gradle scripts. He also incorporates tools such as PNGQuant into his Gradle builds so that resource usage remains optimized.

However, the biggest challenge is creating different versions of the watch face for the different format versions that devices support. To help solve this issue, Tomáš took advantage of product flavors, which let him define a different build configuration for each version. This way, he was able to support the widest range of users while still using the latest and greatest format features on the most recent devices:

/** Set up flavors for different format versions **/


flavorDimensions += "wff_version"
productFlavors{
   // Wear OS 4
   create("wff1"){
       dimension = "wff_version"
       manifestPlaceholders["wff_version"] = "1"
       versionNameSuffix = "-wff1"
       versionCode = 10000 + (android.defaultConfig.versionCode ?: 0)
       minSdk = 33
       targetSdk = 33
   }


   // … other flavors defined here!


   // Wear OS 6
   create("wff4"){
       dimension = "wff_version"
       manifestPlaceholders["wff_version"] = "4"
       versionCode = 40000 + (android.defaultConfig.versionCode ?: 0)
       versionNameSuffix = "-wff4"
       minSdk = 36
       targetSdk = 36
   }
}
Example of using product flavors in a watch face build file, build.gradle.kts, to support multiple WFF versions

Improving velocity and battery life

Amoledwatchfaces is now seeing their investment in this journey to future-proof their watch faces paying off: “Our watch faces are now simply more customizable and more battery friendly. With 8 custom complication slots where you can combine all different complication types, users can have every possible combination of relevant data at a glance.”

User feedback has been great, according to Tomáš, “people mostly refer to battery life improvements after the switch to Watch Face Format.”

And the format has also had a positive effect on development velocity: “I’m developing watch faces faster and cleaner. Updating projects to newer WFF versions is very easy. Fixing bugs is easy too.”

Our watch faces are now simply more customizable and more battery friendly – Tomáš Marcinčin, owner of Amoledwatchfaces

Making the switch to the format

As announced recently, all developers must migrate to Watch Face Format by January 2026. Amoledwatchfaces has benefitted from being an early adopter and recommends that other developers make the switch early too.

Tomáš adds, “Don’t be afraid of switching to a WFF project, managed completely by you. It may seem hard at first sight but when you learn all the attributes, you can define your perfect progress bar arc or gradient digital clock faster than in other tools.”

He also suggests a hybrid workflow, where you work directly in the format and use other tools and editors such as Watch Face Studio. You can first create your watch face in Watch Face Studio, then extract all the resources from the bundle and continue in your preferred IDE.

This week, we’re also announcing Watch Face Designer, which is a Figma-based plugin that you can use in a similar way: start with your design, then export to your preferred format for further refinement.

What's next for Amoledwatchfaces?

For Tomáš, the journey hasn’t ended, and he’s continuing to strive to delight users even more with each new creation. “There’s always room for improvement. When there's a new WFF version or feature which could benefit watch faces and thus users, I’ll be adding that.”

We’re looking forward to seeing the next creations from Amoledwatchfaces!

Getting started the with Watch Face Format