Participants in Group 2 will use the version of the exercise app that has been modified based on the findings from Phases 1 and 2 of this study. Group 2 will be able to use the full features of the interactive app including notifications, ability to submit videos, and non-synchronous messaging/communicating with the researcher. Additionally, participants in Group 2 will be asked to complete 2-5 EMA-based surveys daily to gain information about the participant's barriers and facilitators to exercise. The information from the EMA questionnaires will be used to progress and modify the exercise program at regular intervals for each participant in Group 2.

In addition to the Stage-I assigned app, participants will be asked to complete at least daily EMA questionnaires and e-coaching sessions two times a month throughout Stage-II (weeks 13-24). Participants will only receive the augmented e-coaching intervention if they were not adherent to the exercise guidelines for at least 50% of the weeks during Stage-I (weeks 1-12).

In addition to the Stage-I assigned app, participants will be asked to complete at least daily EMA questionnaires and e-coaching sessions four times a month throughout Stage-II (weeks 13-24). Participants will only receive the augmented e-coaching intervention if they were not adherent to the exercise guidelines for at least 50% of the weeks during Stage-I (weeks 1-12).

The Six-minute Walk (6MWT) and Six-minute Push (6MPT) Tests measure the distance a subject can cover while indoors on a flat, hard surface in a period of 6 minutes. The investigators will determine which test is most appropriate to administer based on the participant's primary mode of mobility (ambulation= 6MWT, manual wheelchair=6MPT). These tests will be used to determine each participant's change in endurance capacity with a greater increase in distance at the later time indicating greater improvements in endurance.

The Six-minute Walk (6MWT) and Six-minute Push (6MPT) Tests measure the distance a subject can cover while indoors on a flat, hard surface in a period of 6 minutes. The investigators will determine which test is most appropriate to administer based on the participant's primary mode of mobility (ambulation= 6MWT, manual wheelchair=6MPT). These tests will be used to determine each participant's change in endurance capacity with a greater increase in distance at the later time indicating greater improvements in endurance.

The Exercise Self-Efficacy Scale assesses an individual's beliefs in their ability to continue exercising on a three time per week basis at moderate intensities for 40+ minutes per session in the future. Participants will indicate their confidence for each domain on a 100-point percentage scale comprised of 10-point increments, ranging from 0% (not at all confident) to 100% (highly confident). Exercise Self-Efficacy scale will be modified to match the SCI exercise guidelines of exercising on a two time per week basis at moderate intensities of aerobic exercise for 20+ minutes per session and/or prescribed strength training. A greater increase in score at the later time point is indicative of greater improvements in self-efficacy (better outcome).

The Exercise Self-Efficacy Scale assesses an individual's beliefs in their ability to continue exercising on a three time per week basis at moderate intensities for 40+ minutes per session in the future. Participants will indicate their confidence for each domain on a 100-point percentage scale comprised of 10-point increments, ranging from 0% (not at all confident) to 100% (highly confident). Exercise Self-Efficacy scale will be modified to match the SCI exercise guidelines of exercising on a two time per week basis at moderate intensities of aerobic exercise for 20+ minutes per session and/or prescribed strength training. A greater increase in score at the later time point is indicative of greater improvements in self-efficacy (better outcome).

The Exercise Self-Efficacy Scale assesses an individual's beliefs in their ability to continue exercising on a three time per week basis at moderate intensities for 40+ minutes per session in the future. Participants will indicate their confidence for each domain on a 100-point percentage scale comprised of 10-point increments, ranging from 0% (not at all confident) to 100% (highly confident). Exercise Self-Efficacy scale will be modified to match the SCI exercise guidelines of exercising on a two time per week basis at moderate intensities of aerobic exercise for 20+ minutes per session and/or prescribed strength training. A greater increase in score at the later time point is indicative of greater improvements in self-efficacy (better outcome).

The Spinal Cord Injury-Quality of Life (SCI-QOL) are a battery of self-reported questionnaires completed by participants to evaluate perceptions of personal independence, pain interference, depression, mobility, ability to communicate needs with others, sense of control over one's life, or other domains in individuals with spinal cord injury. SCI-QOL scales use a standardized T metric, with a mean of 50 and a standard deviation of 10. Higher change scores on a SCI-QOL item bank represent a greater amount of the construct being measured at the later time point (e.g. better independence, more pain interference compared to the earlier time point).

The Spinal Cord Injury-Quality of Life (SCI-QOL) are a battery of self-reported questionnaires completed by participants to evaluate perceptions of personal independence, pain interference, depression, mobility, ability to communicate needs with others, sense of control over one's life, or other domains in individuals with spinal cord injury. SCI-QOL scales use a standardized T metric, with a mean of 50 and a standard deviation of 10. Higher change scores on a SCI-QOL item bank represent a greater amount of the construct being measured at the later time point (e.g. better independence, more pain interference compared to the earlier time point).

The Spinal Cord Injury-Quality of Life (SCI-QOL) are a battery of self-reported questionnaires completed by participants to evaluate perceptions of personal independence, pain interference, depression, mobility, ability to communicate needs with others, sense of control over one's life, or other domains in individuals with spinal cord injury. SCI-QOL scales use a standardized T metric, with a mean of 50 and a standard deviation of 10. Higher change scores on a SCI-QOL item bank represent a greater amount of the construct being measured at the later time point (e.g. better independence, more pain interference compared to the earlier time point).

The 10-Meter Walk Test (10-MWT) assesses subject walking speed in meters per second for 10 meters. Subjects may repeat each measure up to 3 times at their normal self-selected walking speed and 3 times at a fast speed while still able to maintain safety. If the participant primarily uses a manual wheelchair, the Wheelchair Propulsion Test (WPT) will instead be administered. The WPT assesses subject push speed, push frequency, and push effectiveness for 10 meters. Subjects will propel using their usual method and may complete up to 3 trials. For either assessment, a higher change in speed would indicate faster ambulation/wheelchair propulsion (better outcome) at the later time point than the earlier time point.

The 10-Meter Walk Test (10-MWT) assesses subject walking speed in meters per second for 10 meters. Subjects may repeat each measure up to 3 times at their normal self-selected walking speed and 3 times at a fast speed while still able to maintain safety. If the participant primarily uses a manual wheelchair, the Wheelchair Propulsion Test (WPT) will instead be administered. The WPT assesses subject push speed, push frequency, and push effectiveness for 10 meters. Subjects will propel using their usual method and may complete up to 3 trials. For either assessment, a higher change in speed would indicate faster ambulation/wheelchair propulsion (better outcome) at the later time point than the earlier time point.

The Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) is a self-reported 43-item questionnaire to identify the perceived barriers and the extent of barriers to physical activity experienced by people with mobility impairments. Items are weighted, so minimum and maximum values for each domain vary. A higher score is always indicative of more problematic barriers and a decrease in BPAQ-MI scores at the later time point (compared to the earlier time point) would be indicative of less problematic barriers and a better outcome.

The Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) is a self-reported 43-item questionnaire to identify the perceived barriers and the extent of barriers to physical activity experienced by people with mobility impairments. Items are weighted, so minimum and maximum values for each domain vary. A higher score is always indicative of more problematic barriers and a decrease in BPAQ-MI scores at the later time point (compared to the earlier time point) would be indicative of less problematic barriers and a better outcome.

The Barriers to Physical Activity Questionnaire for People with Mobility Impairments (BPAQ-MI) is a self-reported 43-item questionnaire to identify the perceived barriers and the extent of barriers to physical activity experienced by people with mobility impairments. Items are weighted, so minimum and maximum values for each domain vary. A higher score is always indicative of more problematic barriers and a decrease in BPAQ-MI scores at the later time point (compared to the earlier time point) would be indicative of less problematic barriers and a better outcome.