Table 1 Descriptive data for the reviewed apps

App basic descriptive information

 Paid apps on iTunes, and price ($)

6 (26 %)

3.49 (.55)

3.49 (1.0)

2.99–3.99

 Paid apps on GP, and price ($)

5 (22 %)

3.27 (.70)

2.99 (1.0)

2.99–3.99

 Avg. user rating on iTunes (scale: 1–5)

22 (96 %)

4.3 (.6)

4.5 (.5)

2.0–5.0

 Avg. user rating on GP (scale: 1–5)

23 (100 %)

4.1 (.6)

4.2 (.6)

2.4–4.7

 Number of ratings on iTunes (count)

22 (96 %)

23380.7 (92819.4)

1436.5 (5186)

11–438279

 Number of ratings on GP (count)

23 (100 %)

48257.0 (174679.8)

3784 (9037)

31–836597

Number of technical features per app (0–7)

23 (100 %)

4.4 (2.2)

5 (4)

1–12

Presence of technical features

 Allows behavioural tracking

19 (83 %)

-

-

-

 Manual and semi-automated tracking

9 (82 %)

-

-

-

 Allows sharing

8 (9 %)

-

-

-

 Has app community

14 (15 %)

-

-

-

 Requires login

13 (14 %)

-

-

-

 Password

10 (11 %)

-

-

-

 Works in background

14 (15 %)

-

-

-

 Notifications

18 (20 %)

-

-

-

 Needs internet to work

15 (16 %)

-

-

-

MARS app quality ratings (1–5)

 Engagement

23 (100 %)

3.0 (.9)

2.8 (1.2)

1.3–5.0

 Functionality

23 (100 %)

3.8 (.9)

4.0 (1.1)

1.8–5.0

 Aesthetics

23 (100 %)

3.4 (1.2)

3.8 (2.7)

1.5–4.8

 Information quality

23 (100 %)

2.2 (.7)

2.0 (1.1)

1.2–4.1

 Total score

23 (100 %)

3.1 (.8)

3.2 (1.4)

1.9–4.6

Number of change techniques

23 (100 %)

9.3 (4.0)

10.0 (6.0)

1.0–17.0

Presence of effective techniques

 Allows goal setting (GS) only

1 (4 %)

-

-

-

 GS and self-monitoring (SM)

2 (9 %)

-

-

-

 GS, SM and feedback (F)

16 (70 %)

-

-

-

 GS, SM, F and description of behaviour (DB)

2 (9 %)

-

-

-

 SM only

1 (4 %)

-

-

-

 SM and F

1 (4 %)

-

-

-