The evolution of smart cards is the Radio-Frequency IDentification (RFID) devices that can be used to identify people or objects in a contactless form, starting from few centimeters until several meters. The RFID readers and the corresponding tags (or transponders) are high-technology radio devices that can exchange data with each other in order to accomplish identification tasks.
You can get more information regarding the RFID world by taking a look at https://en.wikipedia.org/wiki/Radio-frequency_identification .
There are several classes of RFID readers according to the frequencies in which they work. Some of them are: