Inclusion Criteria:  Clinical diagnosis of autism spectrum disorder Parent endorsements of significant language delay Between the ages of 1.0 and 4.5 years (12 and 54 months) Parents willing to complete intake and follow-up assessments, complete the eight weekly PRT lessons, record and submit parent-child PRT videos, and review these videos on a weekly basis. Access to an internet connection and an iOS smartphone or tablet that can supports the app and records video.  Exclusion Criteria:  Significant medical conditions, seizures, and mental health concerns Non-English speaking Prior parent training in PRT or similar Naturalistic Developmental Behavioral Intervention