Background:
Tobacco use in India is a major health concern; however, little is known about the influence of tobacco-related social and environmental cues on tobacco use. This study uses ecological momentary assessment (EMA) to examine real-time tobacco use and exposure to social and environmental cues.

Methods:
In Hyderabad and Kolkata, participants were recruited, and an EMA application was installed on their mobile phones. Momentary prompts (MP) were randomly used to collect real-time information and end-of-day (EOD) prompts gathered retrospective information on daily basis. Besides personal tobacco use, the surveys asked about exposure to social (e.g., presence of others using tobacco) and environmental cues (e.g., visual and olfactory stimuli). Using the data aggregation approach, bivariate and multivariate analyses were performed to examine the association of tobacco use and cue exposure. Moderating roles of participants’ socio-demographic characteristics were also tested to gain an in-depth understanding of the relationship.

Results:
Among the 205 participants, around a third (MP, 33.7 %; EOD, 37.6 %) used tobacco at least once during the study period. Tobacco-related social and environmental cues related were commonly reported. In the bivariate models, tobacco use was associated with gender, age, and all the examined social and environmental cues except for seeing restrictions on tobacco use. In the multivariate models, tobacco use was associated with age, gender, seeing others using tobacco, and seeing restrictions on tobacco use. Seeing others in one’s immediate group using tobacco was the strongest predictor of tobacco use in both MP and EOD assessments. Gender and age did not moderate the relationship between cue exposure and tobacco use, although males reported higher tobacco use and cue exposure in general.

Conclusions:
This research provides data on the ubiquity of social and environmental tobacco cues in India. The EMA approach was feasible and informative. Future cessation interventions and advocacy efforts should address the high prevalence of tobacco use and exposure to pro-tobacco use cues especially among Indian males. Health education campaigns for promoting tobacco use restrictions in private places as well as changing the norms of tobacco use in social settings are recommended.