It's an addictive game. I just noticed it has been 2 hours since I started playing this game. It's a familiar gameplay, but the theme is relatively new. I'd like to mention some areas for improvement. The movement, though functional, feels a bit stiff. Like what p0x0rz said, a "finish day" button would be better than automatically ending the day when the battery is empty. Make sure the game pauses when the user clicks an area outside the game screen. The user loses keyboard controls when that happens, and he's forced to click somewhere in the screen just to enable it. Worse, the click is registered as a drill even if it's just a click on the settings button. Cheers!
The default action for non-upgradable objects (e.g., traps) should be "move," not "upgrade." Plants and rocks already have the default "clear" action (kindly ignore my previous comment)
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 "Galaxy Life"){kind=icon}