Child development is a maturational, interactive and multidimensional process, influenced by ecobiodevelopmental factors. Studies show the importance of using surveillance and screening tools throughout childhood, reinforcing efforts regarding early identification and intervention. The use of instruments in application format for mobile technology is presented as a possible solution in view of the scarcity of tools with normative data for the Brazilian population, high cost of acquisition of standard-referenced instruments. This dissertation aims to present the initial stages and analysis of construction and content validity of a child developmental delay screening and tracking scale in mobile application format ABCD (Baby Tracking and Developing Child). This dissertation was divided into two studies, in the first part, a review study was conducted to elucidate which instruments for this purpose were implemented in application format (Article 1). The second part is a study with the stages of construction of the ABCD and content validity of the 24-month scale (Article 2). The results of article 1 showed that the two types of instruments (surveillance and screening), were presented in three study categories: 1) descriptive 2) viability / usability 3) psychometric / validity. The findings of this study supported the choice of two instruments used to construct ABCD items, among them PEDS-DM and CDC Milestones. In the second part, the ABCD construction process and the content validity of the 24-month scale are presented. The results are adequate regarding the proposed objective, method, content validity evidence and semantic adaptation for the instrument construction. Finally, it is estimated that the creation of a child development surveillance and tracking instrument in a mobile application format may be a promising alternative in monitoring child development and early identification.