Oppo — R9s Plus Custom Rom

Your camera will look terrible out of the box. Uninstall the stock camera app and download (Google Camera) port for Snapdragon 653. Look for "Parrot043" or "BSG" builds. Enable "HDR+ Enhanced" to reduce noise.

Team Win Recovery Project (TWRP) is a custom recovery tool used to "flash" (install) the ROM files. oppo r9s plus custom rom

Because the R9s Plus received an unofficial Treble patch, you can flash (from phhusson). However, this is for experts only. WiFi calling and FM radio usually break. Your camera will look terrible out of the box