Inclusion Criteria:  Age 18 and older. Can read and speak English and provide informed consent. Diagnosed with cancer, any stage, any disease site. Must be consented to undergo a course of radiotherapy, starting within one month. No limits on duration of radiation apply. Patients must be consented prior to initiating radiotherapy, however.  Has regular access to a mobile device.  Note: This requirement unfortunately leads to the exclusion of underserved patients who cannot afford to have a mobile device. Given that the goal of this study is to establish feasibility of a mobile application, there are no true alternatives, given that these patients would require access to a mobile device if this app were commercially available. However, for impacted patients, the relevant application and resources will be made available on iPads they can access during treatment and a website they can access on any web-enabled device, to ensure they have access as much as reasonably possible. Future iterations of the application will aim to increase access to the resource however possible, but limitations will always apply due to how the core functionality of the app requires a mobile device.  Exclusion Criteria:  Less than 18 years old. Non-English speaking. Inability to operate a mobile device.