Development of a Mobile Health Intervention for Electronic Cigarette Use Among Young Adults

Inclusion Criteria: 1. Age 18-26 years old, ability to understand the English language, willing and able to provide informed consent 2. Current ENDS user (at least 4 out of 7 days per week of use for the past one month); for focus groups, at least half of participants will report current cigarette smoking (at least 1 cigarette per day on at least 1 day per week in the past month) 3. Report interest in quitting or reducing ENDS (at least 6/10 scale in interest of quitting or reducing 4. Does not currently (in past one year) meet criteria for major psychiatric disorder including severe alcohol or substance use disorder (excluding tobacco use disorder), schizophrenia, bipolar disorder, and obsessive compulsive disorder 5. For women, not currently pregnant, planning to become pregnant, or breastfeeding due to lack of information on ENDS use and possible harms from NRT during pregnancy 6. Not currently using smoking cessation medication (i.e., Varenicline, Bupropion 7. No history of adverse reactions to nicotine replacement therapy Exclusion Criteria: 1. Does not own a mobile phone or is unwilling to receive text messages to their device 2. No interest in quitting or reducing use of ENDS 3. Uses electronic cigarettes less than 4 days per week in the past month 4. Reports past-year serious psychiatric illness, including severe alcohol or substance use disorder (excluding tobacco use disorder), schizophrenia, bipolar disorder, and obsessive compulsive disorder 5. Is currently using smoking cessation medication including Varenicline or Bupropion 6. Are a female who is currently pregnant or nursing or planning to become pregnant within the next 6 months