Emerging transportation technologies such as ridesourcing services (i.e. Uber, Lyft, and Via) are disrupting the transportation sector and transforming public transit. Some transit observers envision future public transit to be integrated systems with fixed-route services running along major corridors and ridesourcing servicing lower-density areas. A switch from a conventional fixed-route service model to this kind of integrated Mobility-on-Demand (MOD) transit system, however, may elicit varied responses from residents. This paper evaluates traveler preferences for a proposed integrated MOD transit system versus the existing fixed-route system, with a particular focus on disadvantaged travelers. We conducted a survey in two low-income localities, namely, Detroit and Ypsilanti, Michigan. A majority of survey respondents preferred a MOD transit system over a fixed-route one. Results of ordered logit models revealed a stronger preference for MOD transit among males, college graduates, and individuals who currently receive inferior transit services and have used Uber/Lyft before. By contrast, preferences varied little by age, income, race, or disability status. Survey results further imply that low technology self-efficacy can be a more serious barrier for many people to adopt MOD transit than lacking access to bank accounts, smartphones, or the internet. The most important benefit of MOD transit perceived by re- spondents is enhanced accessibility to destinations, whereas their major concerns include the need to actively request rides, possible transit-fare increases, and potential technological failures. Addressing the concerns of female riders and accommodating the needs of less technology- proficient individuals should be priorities for transit agencies that are considering MOD initiatives.