You can work with issues the same way like you are used to within Jira. Issues can be configured depending on issue type and will display the expected field and have the behavior determined by its workflow.
Find Issues
There are several way in which you can find issues.
Home Screen - Quick Search
If you know part of the issue key or a keyword you can simply go to your home screen and enter it in the top search bar (Android: you will need to press the magnifying glass icon first). The Mobility app will display a matching list of issues, projects, dashboard, and filters. If your Jira instance is large you may want to be more specific to create the result needed.
Home Screen - Search Shortcut
On the Home screen, press the Search shortcut.