Table 2.

Participant responses to each System Usability Scale question for the first and second iterations.

System Usability Scale question	Prompt	First iteration, mean score (SD)	Second iteration, mean score (SD)
1	I think that I would like to use this app frequently.	2.6 (1.7)	3.0 (1.6)
2	I found the app unnecessarily complex.	1.0 (0)	1.0 (0)
3	I thought the app was easy to use.	4.8 (0.4)	4.8 (0.5)
4	I think that I would need the support of a technical person to be able to use this app.	1.3 (1.3)	1.0 (0)
5	I found the various functions in this app were well-integrated.	4.2 (0.8)	4.5 (0.6)
6	I thought there was too much inconsistency in this app.	1.4 (0.5)	1.0 (0)
7	I would imagine that most people would learn to use this app very quickly.	4.8 (0.4)	4.8 (0.5)
8	I found the app very cumbersome to use.	1.2 (0.4)	1.0 (0)
9	I felt very confident using the app.	4.4 (0.5)	5.0 (0)
10	I needed to learn a lot of things before I could get going with this app.	2.0 (1.4)	1.3 (0.5)