The 24-year-old singer and the 21-year-old model locked lips while overlooking NYC's East River in video obtained by TMZ. Later, they were again snapped openly making out, this time in Rockefeller Park.
On Sunday, Bieber Instagrammed himself talking to a young fan, with Baldwin standing by in a floral dress.
"Justin and I were friends for a long time," she told The Times UK. "I met him when I was really young and he was one of my best friends. Everybody knows that at a certain point in time that turned into something else, but that just happens when you're 18, 19. It was what it was. We went through a long period of time when we weren't friends. We didn't speak for quite some time and there was a lot of weirdness that went on. We've moved past that."
Clearly, it appears to be all good now.
For more on Bieber and Baldwin, watch the video below: