HTML5 output lags on mobile devices

I'm trying to troubleshoot a problem of sluggish performance with SL360 HTML5 output.  Where tapping on a button should immediately jump to a slide, sometimes I have to tap repeatedly or press and hold to get the desired response.  The slides in question are simple text and shapes with simple triggers as buttons.  The lag in response is not acceptable to my clients.

What parameters can affect response time when an object is tapped?  Is it something under my control or does it depend on the Storyline output code, the size of the story - which may affect the amount of memory available, the type of server, the device it's viewed on (phones and tablets running Chrome and Safari) or something else?

I want to develop bullet-proof HTML5 training using Storyline. The creation tools are great but so far the playback experience seems buggy and slow.