Hi Alan-Trow-Poole,
It sounds like the device you’re viewing your prototype on has a scaling factor of 2–is this right? In this case, adjusting the “Initial Scale” option in the viewport tag options to “0.5” might help. This is because if your device is applying a scaling factor of 2, the effective screen width might actually be half of it’s listed resolution, which would be 360px instead of 720px. You can check the size in px of the window your prototype is being viewed in by setting a widget’s text to “[[Window.width]]” right when the prototype loads (e.g. in the “OnPageLoad” event).
Another thing you could try is keeping the initial scale at “1.0” but then resizing your prototype to be 360px wide (using adaptive views here might help). If you’re interested, you can read more about the viewport tag and initial scaling option here:
If those approaches didn’t do the trick, would you be able to post a copy of your RP file so I can get a closer look? Feel free to remove any proprietary information before uploading it. TY!