If you have been using MoPub to serve your banner ads eg. for backfills, it is important that you know it is possible to serve retina sizes @2x.
This means you can upload 640x100 instead of 320x50.
MoPub documentation has been poor to highlight this capability. It is found only in their forum.
Anyhow, the steps as follows:
- Create a new creative with the 320x50 banner format
- Set the creative type to Image, and upload your retina image file
- Save and pause this creative
- Preview on the paused creative, right click and copy the image URL
- Create another NEW creative, but set the creative type to HTML
Copy the following into the HTML section:
<a href="CLICK URL HERE" target="_blank"> <img src="IMAGE URL HERE" width=100%> </a>
It is a straight forward
<a> tag, which makes the image fills the width of the banner.
Note: The paused creative is simply to get the image URL, which is used by the actual creative using HTML mode. Do not delete the paused creative.