It's just as described in the videos at YouTube: You can use it via NFC or via Bluetooth (turns the phone automatically added). In addition, there are three modes: Smartphone examined day, day looking smartphone and Area Connector. Last means that a warning occurs when day and Smartphone are too far apart. Here, the mobile phone can vibirieren or in addition to ring and also the day may be a warning signal of itself - these three options can be individually switched on / off. The cards function works perfectly. Switching on and off can be the instrument by a few seconds on the button pressed until it beeps. The Replace the battery (included in delivery and also installed) takes place with a paper clip, the tip of which one pushes gently in the little free triangle on the flat side until it clicks. An operating manual in the sense there is unfortunately not so. Probably it is believed that the one who buys the, already know what they are buying because ...