I'm not sure if this is a bug related problem or not. In the past 2-3 months, a lot of idevice players have been experiencing their screen freezing whenever they spar, walk, pk or guild spar. At first I thought that the freeze was because of the older generation devices(2g,3g,4g) but every player who uses a 5S is experiencing the same problem. The freeze happens every few seconds or minutes depending on where you're walking towards and etc. Like in pking, you could freeze every 5-10 seconds due to the amount of players moving around you. But in Guild spar/single spar, you usually freeze when you're about to hit your opponent or when you're running towards them. I'm not sure if any staff will see this thread post but I hope the problem gets addressed soon, or at least by the GST on May 31st. Down below, I posted a video of how the freeze looks like. I don't know how to explain it because to a lot of people, freeze is communicated as lag or bad internet connection/wifi.
Please watch the video in 1080p b/c its clearer
The freeze happens at 0:06 and 0:20.