Interesting thing I figured out (dunno if this is news or not): Android only allows you to have one version of an app at once. If you try to install an older version while the newer one is installed, it'll error out.
For example, I want the latest version of TripIt for the great notifications, but I want an old version for general use as the new one is slow as molasses and has an utterly convoluted UI.
The simple workaround I found was to download the latest one from the Amazon appstore instead of the official Play store, and then install an older API.
Works like a charm
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