Mobile technology can help bridge health systems gaps and improve reproductive, maternal, newborn and child health outcomes. It has the potential to give every family access to information and services, support health workers, and create a more accountable health system. There are now over 137 mHealth projects at Johns Hopkins using mobile tools in various ways, such as providing education and referrals to communities, decision support and monitoring for health workers, and improving data collection and reporting across the health system. Rigorous evaluation is still needed to demonstrate the impact of mHealth on health outcomes and health systems strengthening.