**Delusion Ideation in the Context of Everyday Life Study** This study looks at ways to help people with schizophrenia, a mental health condition, manage distressing thoughts using therapy sessions and a smartphone app. Participants will have four face-to-face therapy sessions over 4-6 weeks. During these sessions, participants will use their smartphones to record their thoughts and experiences. This method, called Ecological Momentary Assessment (EMA), helps track how they feel in real-time. The app will also remind them of coping strategies, called Ecological Momentary Intervention (EMI). **Key Points:** - Participants must attend four therapy sessions and use a smartphone app between sessions. - The study lasts about 4-6 weeks, and participants will be asked to do self-reported measurements before and after. - To join, you need to be between 18 and 65 years old, speak German, and meet specific health criteria. Participants' information is kept private using special codes, and they have the right to see or delete their data. If you're interested, make sure you have time for all the sessions and meet the eligibility requirements. **Eligibility:** Adults aged 18-65 with schizophrenia, speaking German, and familiar with smartphones are eligible; severe visual impairments or acute suicidal tendencies are excluded.