UPDATE, July 10 21:15 hrs UTC +8:
This issue with Facebook SDK affecting apps on iOS devices has been fixed. You should be able to launch the Viki app on your iOS devices now.
Thank you for being patient.
Hello all,
An issue with Facebook SDK is causing several apps worldwide to crash on iOS devices, including Viki.
We recommend watching on a desktop/laptop web browser at Viki.com, or via the Viki app on an Android device in the meantime. (NOTE: Mobile browsers are not supported)
Thank you for your patience and please stay tuned for further updates on this thread.