Touchscreen apps for preschool age children have the potential to teach children valuable skills including language. However, there is limited empirical data on the educational potential of children's touchscreen apps. Furthermore, selecting an educational app from the app marketplace can also be challenging. This data collection developed tools to assess the educational potential of touchscreen apps for preschool age children and assesses the educational potential and language content of apps available in the app marketplace. In addition, children's behavioural interaction and learning from apps were coded.Children are growing up in an increasingly digital age, surrounded by digital media in the home, nursery and at school. Children's language development is strongly related to the language that they hear in their environment (Hart & Risley, 1995) and research suggests that parental screen media use reduces the quality and amount of language spoken to their children (Christakis, Gilkerson, Richards, Zimmerman, Garrison et al., 2009; Kirkorian, Pempek, Murphy, Schmidt, & Anderson, 2009; Pempek, Kirkorian, & Anderson, 2014; Radesky, Silverstein, Zuckerman, & Christakis, 2014). At the same time, screen media has the potential to provide a valuable source of language input and educational entertainment for young children. The American Academy of Paediatrics (AAP) have recently revised their recommendations for children's screen media use to account for this educational potential (AAP, 2016). The AAP encourage children aged 2-5 years to use screen media but restrict their recommendations to high quality educational screen media which should be used alongside their parents and caregivers and for less than 1 hour per day (AAP, 2016). The question remains however, what constitutes educational screen media for young children? For touchscreen apps, a recent review paper highlighted that apps that promote active, engaged, meaningful and socially interactive learning have the potential to educate young children (Hirsh-Pasek, Zosh, Golinkoff, Gray, Robb & Kaufman, 2015). While 72% of apps aimed at children are classed as "educational" (Shuler, Levine & Ree, 2012), there is little research evidence to back up or contradict these claims. Clearer evidence and guidelines for children's educational apps would provide invaluable knowledge for caregivers, early years practitioners and children's app developers. The aim of this project is to investigate children's language learning apps to develop a scientific understanding of the app marketplace and to apply developmental theories of learning, memory and language acquisition to the development of educational touchscreen apps. The proposed project will combine a systematic review of the children's educational app marketplace with a series of empirical studies to explore how children learn language from touchscreen apps and digital media. The first phase of this project, a systematic review of the app marketplace, will to determine the educational potential for apps currently available to children using theories of language acquisition. These findings will then guide a series of empirical studies investigating children's app interaction and language learning outcomes. Furthermore, we will determine the role of caregiver interaction during children's app use on children's language learning outcomes to provide evidence on the AAP (2016) recommendation for parental co-use during children's screen media use. Across these studies, this project will advance our understanding of educational touchscreen apps designed to teach children language by providing evidence-based guidelines for touchscreen apps and contributing to the development of an evidence based word learning app. This project will also make important theoretical contributions to theories of word learning by incorporating evidence for word learning from digital media and as a result promote the development of evidence-based educational screen media for young children.

Apps were selected from the top 10 lists in the app stores and via two websites that rate apps. Educational app content was analysed using two complementary tools: (1) a questionnaire for evaluating the educational potential of apps and (2) coding criteria for quantifying the app features (see Kolak et al., 2020). Language in apps were transcribed and analysed according to five psycholinguistic measures and types of grammatical construction. 2-4 year old children were tested on a number of different experimental word learning apps developed as part of this project. Children's behavioural interaction, word learning and visual attention were recorded.