I just bought TrueHDR on sale for $0.99 to see if it was better, worse, or at least as good as Pro HDR and the iPhone 4 camera's native HDR setting. Here are the results, without commentary, so you can decide for yourself. The scene I shot was probably not the easiest for any HDR software to work with, having pretty extreme contrast between the light and dark areas, but I think this helped to bring out the differences between the apps and also between their own auto and manual modes.
1. TrueHDR - Auto
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2. TrueHDR - Semi-Auto
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3. TrueHDR - Manual
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4. Pro HDR - Auto
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5. Pro HDR - Manual
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6. iOS 4.2.1 Camera app on an iPhone 4
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