Background: The study describes preschoolers' digital home environment, focusing on parent-child writing interactions using a smartphone and exploring its contribution to children's early literacy. Methods: Participants were 65 Israeli preschoolers (M = 62.37 months) from middle SES and one of their parents. Parents responded to questionnaires assessing the digital home environment (prevalence of digital devices, parental involvement in selecting digital content, children's independent digital activities and screen time). Parents were video recorded while assisting their children in writing a shopping list of three products using a smartphone (keyboard). We analysed how parents helped children segment words into their respective sounds (grapho-phonemic mediation) and type letters independently (printing mediation) and their reference to the orthography. Children's literacy skills (letter knowledge, phonological awareness and early writing) were assessed individually. Results: Findings showed that the homes are rich with technology and children are engaged daily with various digital devices. The level of parental involvement in selecting their children's digital content and the quality of their writing support positively related to children's early literacy skills. Children's independent digital activities were negatively related to their literacy skills. Hierarchical regression analyses showed that the nature of parental writing support predicted children's early literacy beyond parental involvement in selecting digital content and children's independent digital activities. Conclusions: The study reveals the benefits of parental involvement in their children's digital world and highlights the strength of parental writing support and the potential of parent-child digital activities in promoting children's early literacy.