Writing tests in Zephyr for JIRA Cloud is easy, intuitive and available from almost everywhere.
You can also modify existing tests. Since tests are really JIRA issues of issue-type "test", you can clone, search, export, print, bulk modify, link, label, share, vote, or comment on them, just like you would with any other issue.
Tests are written for a JIRA project. They can be further organized and grouped by Versions, Components and Labels that have been set up for that project. A test can belong to one or more of these. The Test Summary tab shows this grouping for a project. These tests can also be searched using the "Issue Navigator" and bulk changes can be made on them.