The purpose of this research is to determine if data from smart devices, including heart rate and movement during sleep and wake times, will be able to track headaches and predict recurrence and exacerbations (make worse). This use of this information may in the future allow patients earlier and more effective treatments if these devices can help predict when the headaches may occur.

Inclusion Criteria:

• Age 18 years and older (no upper age limit defined)
• History of chronic migraine as defined by the International Headache Society's International Classification of Headache Disorders (3rd edition).
• Response to current preventative therapy with ≥ 50% improvement in the frequency of headache days when compared to baseline
• 4 to 14 average number of total headache days per month during peak efficacy of preventative therapy
• Ability to understand study procedures and to comply with them for the entire length of the study and use study devices as outlined in protocol.
• Patient agrees to maintain a daily electronic headache diary.
• Proficient in the use of electronic devices including Apple HomeKit and Apple Watch. - Subjects owns an iPhone with iOS 16 or later operating system installed on iPhone. Apple watch series 8 with watch OS6 or later will be provided by the study.

Exclusion Criteria:

• Chronic daily headache with no periods of headache freedom.
• ≥ 15 average number of headaches days per month during peak efficacy of preventative treatment.
• Medication overuse headache as defined by the International Headache Society's International Classification of Headache Disorders (3rd edition).
• Daily opioid use for > 3 months (e.g., hydrocodone, oxycodone, fentanyl patch) or other daily analgesic use for chronic pain disorders (e.g., NSAIDS or acetaminophen).
• Inability or unwillingness of individual or legal guardian/representative to give written informed consent.