Tetra Lockscreen, one of many apps in the Microsoft Garage project, has evidently been removed from the Windows Phone Store. The app infamously did not work on the Lumia 1520, due to an incompatibility bug that was being worked on, but for other phones like the Lumia 830 it worked just fine.
Reports started coming in early February that the app had gone missing, but some of it appeared to be regional or specific phone related. However, now it seems that for all Windows Phones, the app is indeed gone.
Full story from the WindowsCentral blog...
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