## 1 Introduction  
The increasing use of smart devices by young children has raised widespread concern about their influence on early development [1]. Studies show that prolonged, unsupervised screen time in preschool years may hinder the development of essential self-regulation skills crucial to cognitive, emotional, and behavioural development in children [2]. Although several parental control tools and screen time management applications have been introduced to address this issue, most depend on externally imposed restrictions. These control-based approaches often fail to foster intrinsic motivation in children and may provoke resistance or encourage dependency [3].  
One study reports the need for developmentally appropriate and emotionally engaging interventions to promote digital self-regulation in early childhood [4].  
Consequently, interest is growing in design approaches that align with cognitive capabilities, emotional responsiveness, and imaginative inclinations in young children. Inthis context, digital interactions that promote empathy, narrative immersion, and a sense of agency are increasingly recognised as effective strategies for nurturing healthy digital habits in early childhood.  
Building on these insights, this study reports a novel user experience (UX) framework to support voluntary, emotionally grounded digital self-regulation in preschool children. The proposed framework uniquely integrates [PERSON]'s theory of animistic thinking--which suggests children attribute lifelike qualities to inanimate objects [5]--with therapeutic principles from Acceptance and Commitment Therapy (ACT), emphasising intuitive, character-driven interactions aligned with early development.  
This study offers three key contributions: (1) proposing an innovative integration of developmental psychology and UX design to reconceptualise screen-time disengagement as a socially meaningful and emotionally resonant interaction; (2) operationalising this framework through a publicly accessible mobile prototype, evaluated by paediatric and developmental specialists; and (3) expanding the UX paradigm by introducing a tangible interaction device, 'the Interactive Charger', connecting digital transitions to physical environments through ritualised closure. Collectively, these contributions highlight emotion-centred UX design as a viable alternative to conventional, control-oriented models.  
To implement the proposed framework, a UX prototype was developed and deployed as a mobile application. This prototype features emotionally responsive mechanisms, character-mediated interactions based on developmental principles, and age-appropriate visual design. Designed to foster digital boundary internalisation through empathic interactions and time-awareness cues, the prototype was rigorously reviewed by paediatric and developmental specialists to ensure developmental and emotional coherence. This study proposes a scalable, child-centred UX strategy that shows the potential of psychologically grounded and emotionally attuned design as an alternative to conventional control-based interventions in early childhood digital contexts.  
Guided by these objectives and the practical implementation of our framework, this study aims to address the following research questions:  
1. How can developmentally appropriate practice be conceptualised and applied as a UX design principle to promote voluntary screen-time self-regulation in preschool-aged children?
2. How do child development experts evaluate the proposed UX prototype in terms of its emotional resonance and developmental suitability?