Context – We previously developed the smartphone app for daily recording of symptoms for patients with PMS, and confirmed its usefulness as a paper based recording tool. Now, we have created a second version of the app, which was designed to be more acceptable for ordinary women because many women with PMS are under-diagnosed. Objective – To know if the smartphone app is accepted by non-patients. Methods – This was the pilot study of the second version of the app. We installed this app on participants’ smartphones and asked them to keep records of their symptoms and menstrual cycles every day for the next three months. All participants were screened with the Premenstrual Symptoms Screening Tools (PSST) before using the app. We mailed questionnaires three months later to all participants and conducted voluntary interviews with fifteen people. All the daily data were stored in our server for analysis. Participants – There were 52 participants; 10 patients with PMS and 42 non-patients. The PSST screening showed that among non-patients 7 were suspected of having PMS, and 2 were suspected to have suffered from PMDD. The Participant ages ranged from 14 to 50, and all had regular menstruation cycles. Intervention-using the smartphone app for daily recording of PMS symptoms. Main Outcome Measure- questionnaire and interview data about usability. Results – Valid response of the questionnaire was 46; 10 patients and 36 non-patients. 40% of the patients got pleasure, relief, and ease from using the app but only a few non-patients felt like this. 58% of non-patients felt bothersome, but only 20% of the patients felt at ease. (p=0.032). Among the non-patients, if they were identified as having PMS or PMDD, they tended to like using the app. Interview data showed that the patients wanted to use this app for better communication with their doctors, and non-patients understood more about PMS, which helped them deal with their daily lives much better. 50% of all participants kept records enough to make a diagnosis of PMDD. Conclusions – The need for a daily PMS symptom recording app seemed to depend on whether they think they have PMS symptoms or not.