Therapeutic Contact Intensity in a Psychological Smoking Cessation Intervention With an App

Inclusion Criteria: * aged 18 or over * wishing to participate in the treatment * providing written informed consent * smoking at least 5 cigarettes per day * completion of all pre-treatment assessment questionnaires * having a valid email address * having an Android or iOS smartphone and being willing to use it throughout the treatment Exclusion Criteria: * a diagnosis of severe mental disorder (bipolar disorder and/or psychotic disorder) * concurrent substance use disorder (alcohol, cannabis, stimulant, hallucinogen and/or opioid) * using other tobacco products (electronic cigarette with nicotine, cigars or cigarillos) * having completed an effective psychological treatment to quit smoking during the previous year * having completed a pharmacological treatment to quit smoking in the last year (any smoking cessation medication approved by the Agencia Española del Medicamento) * having a physical pathology involving high vital risk that requires immediate intervention (e.g., recent myocardial infarction) * having visual difficulties that prevent the use of the App.