In this paper, we propose a secure cloud-assisted location based reminder system. The proposed system is secure and responsive. Our system outsources the location testing task - testing whether the current location is near a reminder location - to the cloud server such that the device synchronization is not necessary in the system. This feature makes the proposed system more responsive, especially when the reminder message is of large size, e.g., audio, images. Above all, the proposed system protects a user's location privacy and the confidentiality of the reminder message. The system is designed in a way that the cloud server can perform location testing for a user but cannot learn about her current location, reminder locations, and reminder messages. We prove the security of the proposed system and demonstrate its efficiency using simulations on a Motorola Droid smartphone.