The About screen, which can be accessed from the application menu has the configuration options related to the application updating.
ARC's about screen
By default, the application automatically downloads the next stable release of the application and installs it when you close and open the application again. You can control this behavior by toggling the options in the About screen. When you disable the "Automatically download and install updated" the application won't install updates automatically. However, it will check for updates in the background and will notify you about a new version. You will have to install the update manually.
You can additionally enable installing of pre-release versions of the application. This will install the so-called beta release. These releases are tested by automated testing services but may not be fully tested by authors or users. Usually, the beta release has new features on which you can give us your feedback.