Tiny little bug/glitch on the iOS app :c

Guys, I think something broke inside the iOS app! It's not a big deal, but I though I'd ask if it is something related to my phone or the app itself.

The thing is, when reading a comment on a post, that there's a (null) shown in place of the time and date of posting. Like I said, it's not a big deal, just a little strange bug on the app :)

Pics down below this text:

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via i.imgur.com

Exuf8mh_medium

via i.imgur.com

See the "Posted (null) ago"? What it could be?

ADDITIONAL INFO: On iOS 7 Beta 6, this bug extends to the whole app. Couldn't get a screenshot :(. IDK if it is useful, but I think it could be. This problem occurs on an iPhone 5, both on iOS 6.1.4 and iOS 7 Beta 6.