Inclusion criteria | |
 16 to 24 years old | |
 Living in the UK | |
 Regular access to Android or iOS smartphone | |
 Reports a high level of rumination and/or worry | |
Exclusion criteria | |
 Current diagnosis of Clinical depression, bipolar disorder or psychosis | |
 Current use of medication or psychological interventions to treat a mental health problem | |
 Current suicidality1 |