A terminal apparatus capable of shifting to a power-saving mode with high accuracy in a case where a user puts the terminal apparatus in a bag or pocket A luminance distribution acquisition section acquires luminance distribution around the terminal apparatus. A storage area stores a learned model generated from time series information including the luminance distribution acquired by the luminance distribution acquisition section. A determination section determines, based on the time series information and the learned model, whether a user operation of the terminal apparatus has been terminated or in progress. A power supply section shifts the terminal apparatus to the power-saving mode according to a result of the determination performed by the determination section.