No. Nokia 3.1 does not have the front camera flash.
No. Nokia 3.1 does not have Carl Zeiss branded camera lens.
Yes, Nokia 3.1 does have the 3.5 mm headphone jack.
Yes, Nokia 3.1 does have the face recognition.
In using the Nokia 3.1, you understand how Google and HMD Global let you roam free. When Android operates at its purest, you see a wholesome mobile operating system. Google Assistant and Google Lens are easy to cue, and Google Photos unlocks unlimited cloud storage for high-quality photos and videos.
The Nokia 3.1 is a solid budget phone, with decent specifications, a clean Android experience, and great build quality. However, the lack of a fingerprint sensor is rather puzzling, especially when one can be found on some other phones in this price bracket.