HTML5 Viewing Slooowwww

Aug 10, 2012

Greetings everybody!  

I have been testing my output project on all platforms, and it seems that the HTML5 loading of my project is extremely slow.  The project loads very quickly on android and pc; however loading takes forever on HTML5 and loading time between slides is also very long.....

Do any gurus out there have any ideas???    

Here is a sample project:

Thanks for all the help everybody!!!

19 Replies
Don Needs

Thanks for the responses Phil and Gerry!


I tested it on an Iphone and Ipad through the data connection...Maybe they are not a quick enough connection to allow for prompt loading.  I will try and remove the videos to see if this helps speed up the process!

Thanks for all the input!!  You guys rock and your help is greatly appreciated!

Don Needs


I am getting the exact same result....seems to slow down after the "Begin Workout" button.

The video demo didn't work because I tried to remove the videos to see if it would speed up the process...however it did not.  I have added them back in

Thanks again for all the help guys!

Thanks for the Tempshare link Brian, I'll try it out!

Steve Flowers

I've been experiencing slowness in page transition / loads in HTML5 as well. I've noticed that the biggest factor is the size of media in the next slide. No media and it's pretty snappy. Lots of media and it's slow to transition. 

Most troubling is the lack of feedback that something is happening when it's in "delay mode"

Gerry Wasiluk

Aside comment:  I was revisiting this thread last night and playing around.  I finally saw the same delay with my iPad (I had originally just viewed with my PC and HTML5).

So I went out looking for a HTTP tracker.  I wanted to see if everything downloaded or not to the iPad at the start of the course.  Trouble is, there's few such iPad apps out there that I could find and they don't track everything like ones do for the PC (e.g., HTTP Watch or HTTP Analyzer).

I found one that was "sort of acceptable" and, with it, saw most of the course download to cache at the beginning--except for one critical thing.  I couldn't see the MP4 files download with the tool, so I don't know if they downloaded at the start of the course or real-time when the slide was accessed.

If I was forced to guess, I'd suspect they did download at the start.  If so, why the delay then if they should be in cache?

Don Needs

Hello all!

Gerry thank you for checking it out!  I have come to the conclusion that the Mp4 video is not the source of the delay.  I published 2 projects, one with the mp4 video and one without, and I still got the same results.  The presentation "delays" for a significant period after the user presses the "begin workout" button.  I am confused at what is causing the delay.....

With video

Without video

Don Needs

Another key note...the video starts playing immediately in the background when viewing the HTML5 output on Ipad, even though the layer is hidden and the video should not play until the layer is opened.....I figured this out because I could here the background music of the video playing, even though I had not displayed the "view video" layer

I wonder if this is a cause of the problem.....

Everything displays perfectly in flash...

Ashley Terwilliger-Pollard

Hi Cam,

This thread is a bit older - so I'm not certain if anyone is still subscribed or if the issues are the same. I'd look first to confirm that you're using the latest updates of Storyline to publish your course and on the latest iOS. Also, are you viewing the course in mobile safari or another browser? Safari is the supported option for HTML5 output on the iPad. 

How have you inserted/embedded your videos? Have you seen this across a number of courses or specific to this one? Also where are you hosting  your published output? You could try hosting it in one of these other sites as well to see if that helps resolve playback issues. Additionally have you tried testing it from other wifi networks to see if it's an overall bandwidth issue? Lastly there are some known limitations to HTML5 output in mobile safari detailed here.

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