Here is a coffee cup lid with a WiFi camera that lets you record video covertly anywhere you can fit a cup. You can put this on any standard coffee or tea-cup. The LawMate Coffee Cup Lid DVR has 1080p video resolution. You can interact with it from an app.
The device has time & date stamp functionality. The lens is concealed not to raise any suspicion. The battery life lasts up to 210 minutes depending on the mode you choose.