Radio Frequency Identification (RFID) is currently being used for auto-identification of objects, assets, pets, and people. Its initial success in offering strategic advantages for businesses, by efficient tracking of inventory in the supply chain, has left this technology wide open to many applications that are only limited by people’s imagination. This technology will have a tremendous impact on our society, once it starts to assist people in their daily life. A right step in this direction would be Mobile RFID, where a RFID reader chip is integrated into a portable mobile device like mobile phone, and PDA. Mobile RFID would help consumers in shopping, and allows quick and easy access to information, just by bringing their mobile devices near to an object that has a RFID tag. This paper pioneers in describing Mobile RFID’s new applications and security challenges. It focuses on different Mobile RFID application zones, and their related security threats, and security requirements. Finally it proposes simple security architecture for Mobile RFID applications in Location-based Services zone.