Mobile health may be an effective means of providing access and education to the millions of homeless Americans. We conducted semi-structured interviews with 50 homeless people from different shelters in New York City to evaluate their perceptions, attitudes, and experiences regarding mobile health. Participants' average age was 51.66 (SD = 11.34) years; duration of homelessness was 2.0 (SD = 3.10) years. The majority had a mobile phone with the ability to receive and send text messages. Most participants attempted to maintain the same phone number over time. The homeless were welcoming and supportive of text messaging regarding health care issues, including appointment reminders, health education, or management of diseases considering their barriers and mobility, and believed it would help them access necessary health care. Overwhelmingly they preferred text reminders that were short, positively framed, and directive in nature compared to lengthy or motivational texts. The majority believed that free cell phone plans would improve their engagement with, help them navigate, and ultimately improve their access to care. These positive attitudes and experience could be effectively used to improve health care for the homeless. Policies to improve access to mobile health and adapted text messaging strategies regarding the health care needs of this mobile population should be considered.