Your comments

Please try to update again, it's fine now.
Please try to update again, it should be ok now.
1. Open AppStore to install the app again (It's free)
2. Buy/restore in-app features
Go to "My Videos" first
To restore "Remove Ads": click top left "No Ads", click "Restore previous purchases"
To restore "Share videos": click the blue indicator on the right side of a video, click "Share in iTunes", click "Restore previous purchases". If you have no downloaded video, go to "Channels", select a video, click the bottom right "HD".
3. Go back to install the update again finally.
Click top left "+" on "Channels"
Enter "" and click "Go"
Click a video to play, it will prompt to you to download.
I'm sorry for the unclear reply, hope you have a nice day. You are always welcome :-)
What's your device, and which iOS version running on it?
Try to go to the download page and update again.
Why you don't read the message? You are NOT update from AppStore this time.
Just follow the message go to the url and update.
It seems like a temporary network issue, I suggest you wait for some time then try again.
You want to read the instruction here then install the update.
What's the error message? Can you send me a screenshot of it?