The adoption of tablets by young children has raised enthusiasm and concern among speech and language pathologists. This study investigated whether tablet games can be used as effectively as real play objects in vocabulary intervention for children with developmental language disorder (DLD). A randomized, controlled non-inferiority trial was conducted with 70 3-year-old children with DLD. The novel intervention group (n = 35) received 12 10-min scripted intervention sessions with symbolic play using a tablet game spread out over 8–9 weeks. The standard intervention group (n = 35) received the same amount of intervention with real objects using the same vocabulary scripts. In each session, children were exposed to 22 target words. The primary outcome was the number of new target words learned. This was measured using a picture selection task including 22 target words and 22 control words at 3 time intervals: before the intervention, immediately post-intervention, and 5 weeks later. In both intervention groups, the children learned significantly more target words than control words. No significant differences in gains between the two intervention conditions were found. This study provides evidence that vocabulary intervention for toddlers with DLD using a tablet game is equally as effective as an intervention using real objects.