The device houses 13 MP +2 MP dual rear camera system and an 8 MP Artificial Intelligence (AI)-enabled front camera.
It has a 6.2-inch super full-notch screen, Oppo's AI beauty technology for enhanced selfie experience, 2 GB RAM and 16 GB internal storage.
The smartphone will be available online and in retail stores from July 15.
"With A3s, we aim to offer consumers, especially youth, who are looking for an advanced camera phone that offers a strong battery life," said Will Yang, brand director, OPPO India.
The smartphone is powered by Qualcomm Snapdragon 450 octa-core processor and fuelled by a 4,230 mAh battery.
The handset supports a "music party" function that would enable users to connect multiple smartphones with versions of Oppo's own Android-based ColorOS 5.1 or above to play the same track using hotspot, eliminating the need for speakers.