Information for women with a gynaecological cancer can be difficult to find. Google search results may include unreliable resources. Women diagnosed with a gynaecological cancer and health professionals identified a need for a tool to provide reliable information to help women through their diagnosis, treatment and beyond. An existing Counterpart information app for early breast cancer was expanded to provide information on six gynaecological cancers: cervical; ovarian, fallopian tube & primary peritoneal; placental; uterine (including endometrial); vaginal; and vulval. A co-design approach involving women who have experienced cancer, and health professionals who treat them, was used to create these new information ‘navigators’. Input from focus groups, interviews, and a working group, supported a timeline approach, providing information relevant to each stage of the cancer experience. Usability testing with end users provided clear insights into the best methods of organising and labeling the content. A thorough resource review process required the review of each resource by an Australian health professional with experience working with women with a gynaecological cancer, to ensure information was accurate and reflected Australian practices. In addition, all resources were reviewed by women who had had their own cancer experience, to ensure they were readable, useful, reflected their personal experiences, and were not overly confronting. Challenges included recruitment and coordination of 42 content reviewers, and feedback from the Working Group, focus groups and user testing. The completed app was launched in April 2018, with some features rolling out in the following months. An online platform allows continual updating, so outdated resources can be quickly removed and new resources added soon after publication. Preliminary feedback from health professionals and women has been positive, and a formal review will be undertaken after 12 months.