Despite widespread access to smartphones, teens from communities facing significant behavioral health disparities typically have low mobile health (mHealth) engagement. The purpose of this study was to characterize teen and caregiver perspectives about smartphone use and access, mHealth, and how mHealth could address teens’ behavioral health needs during the pandemic and beyond. Remote recruitment and methodologies were used to engage 17 teens (M age = 15.9 ± 0.9) and 10 caregivers living in urban communities with significant socioeconomic and health disparities. Participants completed a focus group or interview session (based on preference) and self-report questionnaires (e.g., behavioral health history, pandemic impacts, technology use). Qualitative and quantitative data were analyzed using thematic and descriptive analyses, respectively. Both quantitative and qualitative data indicated relevant behavioral health concerns for teens and their families, impacts from the pandemic, and frequent smartphone use. Primary teen and caregiver themes included (1) health and wellness concerns, (2) barriers, (3) use of smartphones, (4) impacts of smartphones, and (5) opinions/suggestions for mHealth. This multi-method and multi-informant study highlighted the lived experiences of teens from marginalized communities and offered key insights to increase the acceptability and real-world engagement of mHealth tools. To address barriers to care for this population beyond the pandemic, clear messaging must be used for mHealth tools (e.g., data privacy, expectations of use). These findings testify to the importance of collaboration with teens and caregivers from communities facing large health disparities in future mHealth design, development, and deployment.