Meet the Safevant Wireless IP Camera: a battery powered indoor camera with WiFi, two-way audio, and night vision that lets you monitor your place conveniently. It comes with free apps for iOS and Android devices. The camera has a 120-day standby time.
The camera has a smart PIR motion sensor to detect events automatically. It can record video to a Micro SD card. You can get yours for under $90 at this time.