chat box for "Four cards of the same rarity give you one random card of the next rarity. you can trade a card by doing a 'swipe up' gesture." - too low, the speech bubble should be coming out from the grey diamond. -minute suggestion "Four cards .... next rarity. Swipe up to trade them in!" an additional speech bubble to describe the mushroom tower might be good in recognition to it's work. e.g. "Do not let the creeps reach here!"
Some suggestions so far: 1) Blessed Fields should be "towers" in the sense that you can view their information panel to read about the stats they give. I feel this would lessen confusion about the tiles, as unless you make the connection from the map description, they just look like fancy tiles. You could also explain whether the BFs extend tower auras. 2) The two different maps should have different preview pictures. Bug reports submitted via Mantis ^^
I added your suggestions to the backlog as tickets, too. For the blessed fields, I probably gonna wait until there are more types of those around, and then make the graphical info representation based on those aura types. The +1 range is pretty simple, but more complex ones are possible too.