I guess you are having a Android device running the 4.x. There is an option named "Do not keep activities" in the developer optons. When it is enabled, the system will destroy every activity as soon as the user leave it. You could find this option(Setting -> Developer options -> Apps, please do not check the option "Do not keep activities".
The view client has multiple activities. When user want to move on another screen, for instance to add broker name, a new activity will launched to do that. If that option is enabled, that means that the previous activity will be destroyed immediately.