When travel returns to normal, many passengers will be more concious of those things that they come in contact with throughout the journey. One common item is touchscreen kiosks - these are used at airline check-in and at passport control, among other places. Most travelers know that airline check-in can typically be accomplished on your personal devices on the airline app or website, but there is also a similar way to avoid the US Customs kiosks as well.
About 5 years ago, US Customs & Border Protection launched the Mobile Passport Control app. The app replaces the questions and process that would typically occur on the kiosks at most major airports. Once completed, the app displays a QR bar code which the traveler shows the CBP agent, along with their passport.
Note that the app does not work for those using Global Entry.
Get the app at the Google Play or Apple App stores.