The US Customs and Border Protection has revealed a mobile app that allows US travellers to submit their passport and customs declaration details using a smartphone or tablet instead of filling out the traditional paper forms.The app, which the CBP launched the app at Miami International Airport on Wednesday, is free to download on iOS and Android. It is available to US or Canadian passport-bearers, with the latter needing B1 or B2 visa status.Travellers simply need to download the app and set up a profile using a selfie and their passport information. The app also allows families traveling together to create multiple profiles.Once the traveler submits their customs declaration form through the app, he or she will receive an electronic receipt with an Encrypted Quick Response (QR) code. This receipt will expire four hours after being issued. Travelers then bring their passport and mobile device with their digital bar-coded receipt to a CBP officer to finalize their inspection for entry into the United States.'We're embracing every technology tool available to make sure our passenger experience is as good as it gets,' said Miami-Dade Aviation Director Emilio T. González in a statement. "MIA is the perfect fit for Mobile Passport: we are America's second-busiest port of entry, handling more than 20 million international passengers each year, " said González. "Mobile Passport Control provides a more efficient and secure in-person inspection between the CBP officer and the traveler. Since the administrative tasks are performed by the traveler prior to the passport control inspection, MPC reduces passport control inspection time and overall wait times, " said the CBP in a statement.However, travellers must have a Wi-Fi or cellular network connection to use the app to submit their customs declaration form and receive the QR code receipt.The Mobile Passport Control app is sponsored by ACI-NA and was developed by Airside Mobile with the Airports Council International-North America