Use a cloud backup app like Google Photos, iCloud Photos, or OneDrive on the old phone
Sign in to the same account on the new phone and sync the photos
Use a transfer app such as Samsung Smart Switch, Move to iOS, or Phone Clone
Connect both phones with a USB cable and copy the photos manually
Use Bluetooth to send small batches of photos
Use AirDrop on iPhone to iPhone
Use Nearby Share or Quick Share on Android devices
Transfer photos through a computer by copying them from one phone and then to the other
Move photos using an SD card if both phones support it
Send photos through messaging apps or email for a few selected images