Implementation of host card emulation mode over Android smartphone as alternative ISO 14443A for Arduino NFC shield

The development of today's technology is increasing technology became more sophisticated and easier for all human activities. Some human activities such as accessing open/lock room's door which is usually done manually or with a smartcard, so we must always carry all sorts of lock (lock house, garage locks, office locks, lock the car) or a smart card these in our daily activities. But sometimes we often forget to bring or keep essential items like that because many of these items and also this time we are more comfortable and behavior can never escape bring smartphones everywhere. Based on those problem, there is an idea to replace of a regular key or smartcard with a smartphone. It can be done if we implemented the key into the smartphone that already used Near Field Communication(NFC) technology module. Implementation of these kind of technology will make possibilities to get rid of carrying many things in our pocket. And it will help people whom easly forget an important things such as keys and smartcard. The role of the key and smartcard can be subtituted if Host-based Card Emulation(HCE) mode implemented on NFC enable smartphone which is introduced in android OS 4.4(KitKat), HCE mode will make smartphones with NFC module can be work act as a smart card that lets people use only one item device in some of its activities. To emulate smart cards and to exchange data between smartphone enable NFC and NFC reader built from components of the microcontroller are Arduino UNO and NFC shield PN532, using a smartcard standard ISO14443A.