Abstract : Biological mass spectrometry mainly comprises three elds of endeavour, namely, proteomics, metabolomics and structural biology. In each of these specialties, the mass spectrometrist needs to access MS 1 mass spectral data, although not necessarily on the same basis. For example, the bottom-up proteomics scientist will occasionally access MS 1 data in order to perform data inspection, quality assessments and quantitation measurements, while top-down proteomics, structural biology or metabolomics scientists will actually spend most of their time mining prole-mode MS 1 data. Furthermore, the advent of ion mobilitymass spectrometry imposes new manners of mass spectral data visualization. An open-source MS 1-only mass data visualization software for the desktop was developed to allow scientists to visualize conventional and drift time mass data. Various mass data integrations are possible, allowing a thorough mass spectral 1