webapp PayPal, e.g Opera program, say Internet-based program, informally Google Docs, e.g Google Chrome program, for one Google Chrome program Google Calendar, e.g Gmail, e.g Chrome extension Online program such as Evernote or Dropbox Google Calendar, e.g., informally Google Docs, e.g. Chrome extension, e.g You might use one on Safari Server-facilitated program Program running in a browser, informally Program like Spotify running in Safari, e.g