BACKGROUND:
Digital health communication can help reduce inequalities by expanding information access, facilitating user feedback to governments and timely connection to care, especially among underserved populations. In Brazil, key challenges include access barriers, health literacy, institutional trust, and cultural adaptation. This work synthesizes evidence from three complementary initiatives demonstrating equity-oriented solutions.

METHODS:
Projeto Saúde e Alegria has worked for four decades in remote Amazon territories,co-producing health education and communication materials with Indigenous communities through exchange between scientific and ancestral knowledge, with pedagogical use across platforms. Instituto de Estudos para Políticas em Saúde supported the implementation of a digital citizen evaluation system within Recife Monitora, a municipal primary care certification strategy based on four-month cycles. Real-time user satisfaction surveys conducted post-consultation via WhatsApp across all primary care facilities, also accessible through QR codes at health units, create an index affecting certification scores and management decisions. ImpulsoGov deployed automated WhatsApp messaging integrated into routine primary care across municipalities, using administrative data to identify people overdue for preventive care in noncommunicable diseases and support appointment confirmation and scheduling while monitoring completion rates for continuous improvement

RESULTS:
Across initiatives, user evaluation systems and timely and culturally grounded communication strengthened territorial action, widened participation pathways, and increased access to preventive care. Evidence includes a 20% average increase in appointments associated with automated messaging; more than 365000 users feedbacks used for health teams qualification; and community mobilization improving cervical cancer screening in previously low-adherence communities. Recurring barriers include accurate linkage of citizens to territories, smartphone/internet access in rural areas, administrative data quality, and institutional trust.

CONCLUSIONS:
Integrating community co-production, citizen feedback, and data-driven messaging offers a replicable pathway for equity-oriented digital communication in Brazilian primary care. Recommendations include culturally adapted content, multi-channel strategies, institutionalized feedback loops with visible response, and investments in data quality and infrastructure.