Table 2.
A representative set of 52 design features based on the Coventry, Aberdeen, and London—Refined (CALO-RE) taxonomy.
| Design features of exercise-promotion apps | Code |
| Apps provide information on consequences of exercise in general. | A1 |
| Apps provide information on customized consequences of exercise. | A2 |
| Apps provide information about others’ approval of my exercise. | A3 |
| Apps provide information about others’ exercise status. | A4 |
| Apps provide information about avoided movement in exercise. | A5 |
| Apps help set exercise goals. | A6 |
| Apps help set graded tasks by decomposing goals. | A7 |
| Apps prompt review of exercise goals. | A8 |
| Apps can check the extent to which previously set exercise goals were achieved. | A9 |
| Apps remind me to record my exercise behavior. | A10 |
| Apps can record my exercise behavior automatically. | A11 |
| Apps can set the health goals to be achieved by exercise. | A12 |
| Apps can prompt review of health goals. | A13 |
| Apps can check the extent to which my expected goals were achieved. | A14 |
| Apps remind me to keep records of my exercise outcome. | A15 |
| Apps can automatically record my exercise outcome. | A16 |
| Apps can assist me in detailed exercise planning. | A17 |
| Apps can remind me to think about potential barriers in exercise planning. | A18 |
| Apps can remind me to identify the ways of overcoming potential barriers when exercise planning. | A19 |
| Apps prompt rewards contingent on effort toward exercise preparation. | A20 |
| Apps provide rewards contingent on successful exercise. | A21 |
| Apps provide graded use of contingent rewards over time. | A22 |
| Apps prompt generalization of exercise. | A23 |
| Apps remind me of past successful experience of exercise. | A24 |
| Apps provide exercise records. | A25 |
| Apps check the discrepancy between exercise performance and the set goals. | A26 |
| Apps provide me with data about the discrepancy between my exercise performance and others’. | A27 |
| Apps provide information on where and when to do the exercise. | A28 |
| Apps provide instructions on how to do the exercise by text or voice. | A29 |
| Apps show how to do the exercise through visual demonstrations. | A30 |
| Apps can set context cues which remind me to exercise. | A31 |
| Apps can set location cues which remind me to exercise. | A32 |
| Apps can set people cues which remind me to exercise. | A33 |
| Apps remind me to alter environment in ways so that it is more supportive of the exercise. | A34 |
| Apps create the exercise goals as agreed behavioral contract. | A35 |
| Apps prompt me to rehearse or repeat the exercise behavior numerous times. | A36 |
| Exercise reminders are gradually reduced in intensity, duration, and frequency over time. | A37 |
| Apps facilitate social comparison. | A38 |
| Apps make it easy to elicit social support to my exercise from other people. | A39 |
| Apps remind me to focus on partners who are the exercise role models. | A40 |
| Apps facilitate the discussion with exercise role models. | A41 |
| Apps induce perceptions of future regret about not doing exercise. | A42 |
| Apps provide risk information which evokes a fearful response. | A43 |
| Apps prompt self-talk to encourage, support, and maintain exercise. | A44 |
| Apps prompt mental imagery (to imagine initiating or maintaining exercise is easy). | A45 |
| Apps provide strategies in advance to avoid sustainability problem of exercise. | A46 |
| Apps provide stress management to reduce anxiety to facilitate the performance of the exercise. | A47 |
| Apps remind me to attend motivational interviewing which can minimize resistance and resolve ambivalence to change. | A48 |
| Apps assist time management to make time for exercise. | A49 |
| Apps provide general communication skills training. | A50 |
| Apps stimulate anticipation of future rewards. | A51 |
| Apps can set exercise time reminders. | A52 |