Early numeracy competencies are of great importance for children's competency development. Here, early digital intervention approaches offer the potential to support all children and their families. We investigated whether the provision of specific numeracy learning apps and parent information about children's numeracy development improves both, children's numeracy competencies and the quality of families' home numeracy environment (HNE) while considering the potential impact of parental (STEM) occupation. Children's numeracy competencies were measured twice in two cohorts (N[subscript 1] = 190 children; M[subscript 1age] = 63.6 months; SD[subscript 1] = 4.4; N[subscript 2] = 310 children; M[subscript 2age] = 59.4 months; SD[subscript 2] = 3.9) with a six-month interval between t1 and t2. Parents were surveyed about the family characteristics and the HNE. Families in the numeracy intervention group (N[subscript total] = 151) received tablet computers with specific numeracy learning apps and parent information. No significant intervention effect on the quality of the HNE was found. However, children from intervention families showed significantly greater numeracy competency gains, even when considering child and family characteristics and independent of parental occupations. Consequently, high-quality learning apps can support the development of children's numeracy competencies already at preschool age. Further ideas on how to reach families and enhance the HNE are discussed.