Use of a Comprehensive, Mobile Application to Assist Cancer Patients With Diet, Nutrition and Activity

Inclusion Criteria: * Diagnosis of invasive malignancy of the brain, head and neck region, lung, breast (DCIS and invasive disease allowed), prostate, gastrointestinal system or gynecological region * Planned to receive, or have received, radiation therapy treatment with curative intent * Note: Patients undergoing systemic therapy are eligible * Note: Any dose/fractionation of curative-intent radiation therapy is eligible * Patients must have a smartphone or other device with the ability to receive text messages, download and use mobile applications * Eastern Cooperative Oncology Group (ECOG) performance status 0-2 * Ability to read and write in English * Provide written informed consent to participate in the study o NOTE: Patients enrolled on another clinical trial are eligible Exclusion Criteria: * Metastatic cancer * Undergoing treatment with palliative intent * Poorly controlled diabetes (defined as fasting glucose level \> 200 mg/dL despite attempts to improve glucose control by fasting duration and adjustment of medications) * Uncontrolled hypertension * Any medical condition requiring fluid restriction or nutrient restrictions