Table 2.

List of problems encountered by participants (N=10) during the 14 tasks and description, categorization, and frequency of occurrence of these problems during task completion.

Item	Category (number according to the Bastien and Scapin classification)	Description of the problem	Task in which it occurs (frequency of occurrence)
1	1. Guidance	Five (50%) users did not find the place of the button to put a reminder. For most of them, it was too small, and its location was not easy to find.	Set alarm for the vital signs (5)
2	1. Guidance	Three (30%) users said the “information” symbol was too small next to the treatments list and that they did not find it easily	Find medication information (3)
3	7. Significance of codes	Two (20%) users did not find the scanning possibility option in the app explicit enough	Enter medication (2)
4	2.2 Information density	Six (60%) participants had difficulties recording medication manually in the app. They say they had to put too much information on one page.	Enter medication without medication package (6)
5	7. Significance of codes	One (10%) participant did not understand names of some drugs because the name of the medication was not written next to the active substance	Find medication information (1)
6	1.3 Immediate feedback	One (10%) participant found the validation of medication intake not explicit enough	Confirm your medication intake (1)
7	7. Significance of codes	Two (20%) participants did not understand the term “if necessary,” such as medication to take in reserve	Enter pro re nata, if necessary, without medication package (2)
8	8. Compatibility	One (10%) participant asked to set an end date for his treatment, but this function does not exist	Enter medication (1)
9	5.2 Error message quality	When entering the date, one participant (10%) did not write it correctly (separated by “/” symbols and not “.” symbols). Therefore, the date could not be validated and no explanation appeared	Enter weight (1)