Blinks API Reference (lite)
Blinks API Reference - a reference with function parameters
API Source Code - absolute truth (would I lie about something like that? 🙂 )

Display

setColor(color)
setFaceColor( face, color)

Colors

makeColorRGB(red, green, blue) - values [0-255]
*makeColorHSB(hue, saturation, brightness) - values [0-255]
*dim(color, value) - values[0-255]
*RED
*ORANGE
*YELLOW
*GREEN
*CYAN
*BLUE
*MAGENTA
*WHITE
*OFF

Button

buttonPressed()
buttonReleased()
buttonSingleClicked()
buttonDoubleClicked()
buttonMultiClicked()
buttonClickCount()
buttonLongPressed()
buttonDown()

Communication

setValueSentOnAllFaces(value) 
setValueSentOnFace(value, face)
getLastValueReceivedOnFace(face)
isValueReceivedOnFaceExpired(face)
*didValueOnFaceChange()
*isAlone()

Time

millis() - monotonically incrementing timer
Timer.set()
Timer.isExpired()

Types

byte
word
int
long
float
double
bool
Color
Timer

Convenience