When a user taps the "forward pointing" arrow on a mini-popup:
They are presented with a more detailed popup:
I suggest that the down arrow button on the right hand side, and the X button on the left hand side of the detailed popup be removed. I suggest these be replaced by a single button on the left hand side that is a "backward pointing" arrow in the same style as the "forward pointing" arrow that the user tapped to open the detailed popup.
The rationale behind this is two-fold:
The down arrow does not clearly indicate what will happen when tapped. Some people may even mistake it for a "download" button, as one of our users has already.
The X button to close the detailed popup may be tapped with the intention of returning to the mini-popup, but instead it closes the popup entirely. This is problematic on maps with many features, as the user may not be able to identify the same feature again without having to conduct an entirely new search.