A Google Cloud outage is causing major headaches for some of the most popular apps.

Snapchat, Spotify, Discord, and Pokémon Go all went down for portions of the afternoon Tuesday, after an unspecified issue with Google's App Engine.

The cause of the issue is unclear, but problems began at 12:35 p.m PT and lasted for nearly hour, according to Google Cloud's status page. Whatever the issue, though, it also took out several apps which rely on Google's services for back-end infrastructure.

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Tweet may have been deleted

Discord confirmed the issue was related to the Google outage, while Snapchat's support simply said it was "working with a partner on the fix." Pokémon Goand Spotify also confirmed issues, but didn't cite Google specifically.

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Tweet may have been deleted

At 12:58 p.m. PT Google said in another update that "the issue with Google App Engine should be resolved for some users and we expect a full resolution in the near future."

At 1:23 p.m. PT, Google confirmed its service had been fully restored, though the cause was still unclear. "We will conduct an internal investigation of this issue and make appropriate improvements to our systems to help prevent or minimize future recurrence."