I got it to resize slightly better however it's not centered to the layout and some of the test ads text gets cut off. I have a layout of 640X1136 and the Iframe is 640X90. I positioned it to the bottom of the screen and I set the leadbolt banner to auto stretching.
<!DOCTYPE html><!--HTML5 doctype-->
<title>Leadbolt Framed Ad for Android Games</title>
<meta http-equiv="Content-type" content="text/html; charset=utf-8">
<div style="position: fixed; bottom: 0px; left: 0px; width: 640px; height: 90px;">