## 1 Introduction  
Hand-gesture-driven interaction has matured into a dominant input method, expanding its practical applications across high-tech domains. This evolution has been particularly evident in industries like gaming, robotics, and IoT-powered home appliances [1]. Within the Human-Computer Interaction (HCI) field, gesture recognition has become a central research topic, with major technology firms integrating gesture-based controls into their ecosystems. Companies like Microsoft, Google, Apple, Meta, and Sony have integrated their own gesture recognition technology into their platforms, such as the Google Soli project, Microsoft Kinect and the HoloLens Head-Mounted Display (HMD), the Meta QuestHMD, and recently the Apple Vision Pro HMD. These technologies showcase how gestures can act as intuitive, organic methods for engaging with digital and virtual environments [2]. For instance, Meta Quest Software Development Kit (SDK)'s hand recognition and tracking technology perfectly and conveniently replaces the conventional VR controllers, demonstrating how hand-gesture-driven interaction could enhance immersive in-play experiences within VR/MR environments [3]. Likewise, Apple Vision Pro relies on pinch gestures as a core mechanism for navigating spatial UIs, intentionally minimizing the reliance on traditional XR controllers [4]. In consumer tech, smart TVs and media devices increasingly support free-hand gestures for interface navigation and control, moving beyond the conventional presses of a button on a remote to hand swipes and waves. For example, Sony and Apple have secured patents for mid-air gesture controls designed for navigating TV home interfaces, effectively serving as alternatives to traditional physical remotes [5; 6]. Moreover, their integration with wearable technology further enhances the gesture recognition accuracy. Compared to free-hand gestures, lightweight wearable devices--such as smart rings equipped with IMU (Inertial Measurement Unit) sensors--offer a more accurate and user-friendly way to detect fine gestural actions like subtle muscle vibrations and directional finger movements [7]. In particular, a key reason for spotlighting smart rings as an interaction method stems from the high computational demands of bare-hand gesture recognition, which typically involves numerous cameras and substantial processing power for visual sensing [8]. Also, many users express a preference for lighter, glasses-style XR gear over bulky headsets when engaging with XR experiences [9]. Addressing this preference, Meta's Orion project has introduced a wristband that uses Electromyography (EMG) technology to improve the precision of gesture recognition for lightweight XR devices [10]. Drawing from such developments, this study emphasizes enhancing natural user interactions through everyday wearable form factors--such as the increasingly popular eyewear-like XR devices. Consequently, we identified the smart ring as an optimal target form factor to facilitate gesture-based interactions due to its potential for seamless integration into everyday user routines. Considering this, the widespread use of hand gesture technology highlights the increasing relevance of gesture-based interfaces, supporting the idea that Natural User Interfaces (NUIs) could offer an intuitive and efficient way for users to interact with digital systems [11]. It thus becomes crucial to examine how users preferably perform and perceive hand gestures across different interface contexts, especially in two of the most active application domains: a TV-based 2D screen interface environment and a spatial interface environment. These two platforms present notably different usability contexts. A TV-platform-based UI typically involves a lean-back control experience on the couch in the living room.