Adults Regulating Their Weight Everyday With Mobile Internet Support

Participation is open to those who meet the following eligibility criteria: * aged ≥ 18 years; * living with obesity (BMI ≥ 30 if of white ethnicity; ≥ 27.5 for all other ethnic groups); * full- time residents in the UK, without the intention to move outside the UK within the next 12 months; * able to access the internet with a smartphone; * able to access and use a digital weighing scale; * can understand English; * not presently signed up with an intention to attend, or have in the previous three months attended, a weight management programme; * not currently participating in another weight management study; * not lost \> 5 kg (10 pounds) body weight in the previous six months; * not undergone bariatric surgery, or presently scheduled to have bariatric surgery; * not pregnant, or planning a pregnancy in the next 12 months; * not previously been diagnosed with an eating disorder; * not recently been diagnosed with a disease, or expected to undergo treatment for a disease, associated with substantial weight loss e.g., cancer treatment.