Xiaomi’s sub Brand Redmi has certified Redmi S3 phone form Wi-Fi. This might the successor of Xiaomi Redmi S2. The certification told us that Redmi S3 launching pretty soon. The Xiaomi S3 comes with Android 9 (Pie) and MIUI 10 as well.
The other specs are not revealed yet. But comes with better specs than the Redmi S2. Other information is revealed when the Phone is launched. Wi-Fi clue shows us that Xiaomi Redmi S3 is on the final zone.