The CBP One app was set up under the Biden administration to create an orderly way for migrants to enter the U.S. and to reduce illegal border crossings.

Migrants who waited months to cross the U.S. border with Mexico learned their CBP One appointments had been canceled moments after Donald Trump was sworn in as president.

Just as Donald Trump's inauguration concluded, Honduran asylum seeker Denia Mendez's phone buzzed with alarming news: the CBP One app, her lifeline to a new life in the US, was down.

The Trump administration has ended use of the border app called CBP One that allowed nearly 1 million people to legally enter the United States.

CBP One was used by the Biden administration to allow hundreds of thousands of migrants into the country to pursue asylum claims.

The CBP One app has been highly popular, functioning as an online lottery system that grants appointments to 1,450 people daily at eight border crossings. These individuals enter the U.S. under immigration "parole," a presidential authority that Joe Biden has exercised more frequently than any other president since its creation in 1952.

The CBP One app has been wildly popular. It is an online lottery system to give appointments to 1,450 people a day at eight border crossings.

Victoria Meijia Garcia, 31, opened the CBP One app at 10 a.m. Monday as she did every day for the past several months, seeking an available appointment with an asylum official. But today, the top of the familiar homepage blared a message that filled her with dismay.

"The first 100 days are going to be the most aggressive, change oriented policy proposals and procedures that we've ever seen," KOAT political expert Brian Sanderoff said.

Donald Trump has granted sweeping new powers to multiple government agencies to help homeland security deal with the crisis at the border.