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Updated: Nov 25, 2025

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Published on: October 5, 2020
Comfort and discomfort during smartphone use on a bed
Sumalee Udomboonyanupap1,2, Stella Boess1, Luciana Ribeiro Monteiro3
1Faculty of Industrial Design Engineering, Delft University of Technology, The Netherlands.
Background:
The number of smartphone users is immense. People can do ever more with a smartphone. Smartphones are used everywhere, including in bed and on the sofa. The awkward postures taken in these situations affect comfort and discomfort. In designing a bed, it might be useful to know which position is comfortable for smartphone use on a bed.
Objective:
The objective was to define the most comfortable trunk angle for smartphone use on a bed.
Methods:
To study comfort and discomfort, 52 participants were asked to use the smartphone on a bed. The trunk angle of this bed was adjusted to 6 positions from flat to upright and for each angle the comfort and discomfort was recorded.
Results:
The results showed that the participants prefer a trunk angle range around 120 and 142 degrees. At the best trunk angle 29% of the participants felt comfort in the legs, 25% in the upper back and 16% in the shoulders. However, in this position 36% also mentioned discomfort in the lower back and 24 % in the neck.
Conclusions:
For smartphone use a bed is preferable which enables a trunk angle of around 120-140 degrees. For the legs this is comfortable. However, for the neck and upper back the problem of discomfort still needs attention.
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