The video doorbell or surveillance camera cam transmit the dynamic HD video and two-way audio to your iPhone or iPad directly. You can also view video history with SD card video playback function. No matter where you are, NVDP lets you watch your home easily. With NVDP, you are always Home. Features: 100% Wire-free for working. 180°wide view. IP65 Waterproof. 6 months long working time. Two-way full-duplex communication. 720P HD video, low bandwidth cost. Seconds fast response even at sleep mode.