you mentioned mail - yes, this is one option. When setup properly you can open an issue via mail, for example:
The most standard way surely is to login via browser:
A more advanced way to access Jira is via REST API. Think of scenarios where a user wants to gather data by a script or an external App/tool/software:
Catch up with Atlassian Product Managers in our 2020 Demo Den round-up! From Advanced Roadmaps to Code in Jira to Next-Gen Workflows, check out the videos below to help up-level your work in the new ...
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