In this paper, we examine whether ICT use at work is related to different facets of work intensity, including time pressure, multitasking, and interruptions, as well as the number of hours worked overtime as an indicator of work extension. For ICT use, we distinguish different devices by their associated flexibility options for employees considering using a desktop PC, a laptop, and a smartphone/tablet. Moreover, we explore whether further technology-related variables at the intersection of technology, the organization, and the individual are related to work intensity or might even partly explain why ICT use is related to work intensity. The analyses are based on the 2019 survey “Digitization and Change in Employment (DiWaBe).” OLS results indicate that the work-related use of a smartphone or tablet is related to significantly higher levels of work intensity and work extension, regardless of the indicator considered. In contrast, we find no evidence that working with a laptop is associated with increased work intensity. This suggests that the flexibility options associated with a given mobile device are crucial. Further analyses reveal that technology-induced interruptions and information overload in particular are strongly related to work intensity.