text neck; smartphone neck
Colloquial term for neck pain or injury caused by prolonged forward head posture while using a smartphone or similar device.
Lately, my shoulder stiffness is terrible because of text neck.
To prevent text neck, it seems good to bring the screen up to eye level.
Compound of スマホ (sumaho, 'smartphone') and 首 (kubi, 'neck'), referring to neck problems caused by looking down at a smartphone.