Physical activity apps offer significant potential to promote physical activity and active aging; however, their acceptance among older adults remains limited, often due to insufficient digital literacy. This study aimed to examine whether targeted, app-specific digital literacy training can improve eHealth literacy, acceptance of physical activity apps, and behavioral intentions among older women, drawing on the UTAUT2 (extended with personal innovativeness). A total of 63 older women (M = 67.0, SD = 4.6) were randomly assigned to an experimental (n = 32) or control group (n = 31). The experimental group participated in a nine-week digital literacy training focused on practical use of physical activity apps. Measures were collected before and after the intervention. Data were analyzed using repeated-measures MANOVA and ANOVAs. A significant Group × Time interaction was observed for technology acceptance (Wilks’ Λ = 0.41, F(7,54) = 11.14, p < 0.001, ηp² = 0.59). The experimental group showed significant improvements across all measured constructs. The largest effects were found for eHealth literacy (ηp² = 0.39) and intention to use physical activity apps (ηp² = 0.24). App-specific digital literacy training can enhance technology acceptance and support physical activity–related intentions among older women, highlighting its potential as a strategy for reducing digital barriers and promoting active aging.