I wrote a feedback email to the developer with many small suggestions for improving Maps TD. I am copying them here in case others are interested or have the same suggestions.

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If fast-forward is enabled when the round ends, skip the animation of the "Next Round!" panel falling and have the panel just appear. When I have a strong turret formation and just want to send a few waves of enemies through it to save up money, I get annoyed from having to wait for the Start (start the next round) button to finish bouncing before I can click it. Though the speed of the disappearance of that panel is fine. Perhaps the disappearance animation but in the other direction would work, too, since it's fast.

When a turret is selected, you make the inner circle white. I suggest you also make the border of the outer circle black, so we can see the range of the selected turret easily.

Turret inspector window suggestions (attached to this email is a mockup image incorporating these suggestions): (attachment mirrored for this comment at http://postimage.org/image/hizbeeotj/)

Make the turret type and X (close) button always stick to the top, even after scrolling, so I can easily close the inspector wherever I am in it.

To the left of the turret type name (e.g. "Yellow Tower"), put an icon of that turret (e.g. a yellow turret icon).

Always show the current attributes of the turret, no matter how you scroll - fix them to the top. Then, for each attribute, instead of listing every new attribute and the cost, list only the attribute that will be changed plus the cost. It might also be nice to show the old value of the attribute, for reference, but I don't see a place to fit that in the interface. I think this will make the effect of each upgrade easier to comprehend, and also require less scrolling. If that big a change sounds bad to you, here is different way of achieving that: in the attributes list of each upgrade, make the attribute that will be upgraded bold, italic, another color, or otherwise emphasized.

I don't know if this is possible with the Google Maps API, but it would be nice to have some indication of how upgraded a turret is just from its icon. I had one fully-upgraded blue turret next to a plain blue turret, and I wanted to upgrade the plain one, but I had to look at the inspector of one of them to find out which one was the plain one. Some possible indicators of upgradedness are the shade of the color (darker or lighter), the color or darkness of the circle representing size taken, or the size of the dot in the middle of the turret. The number to indicate how upgraded a turret is would probably just be the number of upgrades divided by the number of possible upgrades for that turret type.

Bug: on Firefox 11.0 on Windows 7, the six turret icons on the side all look like the goal/house icon instead, which is confusing for new players. The icons on the map look fine, and all icons look fine in Chrome. An image showing this bug is attached. (attachment mirrored for this comment at http://postimage.org/image/h0m7bv53f/)

I am seeing this turretless winning bug, too: http://news.ycombinator.com/item?id=3784435 (and the sale price bug mentioned in its reply).

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