Among its services, ML Kit provides a face detection API: you can use it to detect faces in an image, identify single parts of a face, such as eyes, mouth, and nose, get the contours of detected faces and parts, and identify whether a face is smiling and has the eyes open or closed.
ML Kit provides a face detection service, not a face recognition one. This means that while you can identify faces in a picture, you cannot recognize people.
There are several use cases to implement face detection: among others, you can create avatars, edit the pictures, or categorize your images.
In this recipe, after taking a picture, you identified the faces in the image and gave your user some information about them: whether they had their eyes open and were smiling.
Face detection is performed on the device, and no connection is required to use it.
You used a pattern similar to the previous recipes in this chapter: you got an image, sent it...