What has changed?
The tracker is no longer globally available in the bottom-right corner of the screen. You can now access the tracker via the issue view or the issue sidebar in Boards. You can now create multiple trackers and view any of your trackers in the Tempo tracker gadget.
In addition, the tracker is no longer session-based, which means that any trackers you create are synced, and accessible via JIRA views, the Tempo mobile app, and Tempo for HipChat.
You can read more about how to use the tracker here.
Why has it changed?
The Atlassian Connect framework displays all content from add-ons on JIRA pages within an iFrame: that is a window that Tempo can create, but only at locations on the screen specified by Atlassian. Other content from add-ons must be displayed on the add-on’s page. This will deliver many improvements for JIRA - in the future JIRA should be more stable, and its performance will no longer be affected by the performance of any macros running within JIRA. This, however, means that add-ons are more restricted when implemented in JIRA views.
We did not change the tracker because we wanted to, but because we had to. These are simply the locations where we can display the tracker today. In the process, we also added some tracker improvements.
What changes or improvements should I expect in the coming weeks?
We will make the tracker available in new locations as Atlassian makes them available. We are also planning to release a browser extension with tracker capabilities which should give a similar experience to the old tracker.
We won't be able to bring the old tracker back, and whether we can re-implement that functionality depends on Atlassian.