The 0.1% CTR apps relate to mobile games where there is little interaction with the ad is 'Word Seek Social Lite' The 4.5% CTR app relates to generalized RSS readers similar to FMyLife (ex: Softbaum's FMyLife for which we have a rev sharing agreement).
Hope this helps, of course since these are highly profitable, I can't share too much details.
Without context we can't validate your claims and hope to reproduce them. Thanks.