Can I use my mobile as RFID card?

Can I actually use my mobile device as an RFID card? I've heard of NFC technology being used for contactless payments and access control, but is it feasible to replace a traditional RFID card with a smartphone? How secure is this method, and what are the potential limitations or drawbacks I should be aware of before making the switch? Is there any special hardware or software required to enable this functionality, and how do I ensure compatibility with the RFID systems I need to interact with?