Yes, Samsung Galaxy C7 Pro does have the rear camera flash.
Yes, Samsung Galaxy C7 Pro does support OTG.
No. Samsung Galaxy C7 Pro is not a water-resistant phone.
No. Samsung Galaxy C7 Pro does have the hybrid sim card slot. You can use either 2 sim cards or 1 sim card & 1 memory card.
No. Samsung Galaxy C7 Pro does not support 4k video recording. You can record up to full HD recording.
Samsung has managed to strike a good balance between performance and battery life with the Galaxy C7 Pro.
The Galaxy C7 Pro has a lot of strong points — the build quality is great, the Full HD AMOLED display is excellent, the overall performance is adequate, and the battery life is amazing.