The iPhone screen is tiny compared with the iPad's, so this necessarily makes GMail on the iPhone harder to use. For example, it's impossible to look at folders and messages at the same time when holding the phone vertically. To see them both, the phone has to be horizontal. But on an iPad it looks amazing. After switching back to iOS Mail after using Gmail 2.0 for only a few minutes I missed certain parts of Gmail 2.0 already.
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