Current list is incomplete. It is also a bit outdated.

S - short press
L - long press
x - do not press

Short press is like any other click, you don't hold it down.
Long press is just a little bit longer. You can even hold it for a few seconds if you wish, although 100 milliseconds is already enough.

Lower button is also called the first button. The LED shines green when you press it.
Upper button is also called the second button. The LED shines blue when you press it.

Hover over a key to get textual description.

Key Device Action Client Action
Space (Sx Sx)Repeat
Backspace (xS xS)Negative Repeat
Enter (SS SS)
Shift (Sx xS)[[Shift_Key?]]
Symbols (xS Sx)[[Fn_Key?]]
e (Sx SS)Accept call
t (xS SS)Tell time
a (SS Sx)Toggle AAA mode
o (SS xS)
i (Sx Lx)Toggle indicator
n (Lx Sx)Next song
s (xS xL)Volume -10% (Mnemonic: silence!)
h (xL xS)Reject call
r (SS LL)'Right' key (Next slide)
d (LL SS)Tell date
l (Sx xL)Volume +10% (Mnemonic: louder!)
c (Lx xS)Pause/continue music
u (xS Lx)Turn off
m (xL Sx)mute
w (Sx LL)write current timestamp
f (Lx SS)Close (Alt+f4)
g (xS LL)Tell battery info
y (xL SS)Reset fuel gauge
p (SS Lx)previous song
b (SS xL)Switch
bluetooth power
v (LL Sx)Test device
k (LL xS)Text input
j (Lx Lx)[[Flashlight?]]
x (xL xL)Typing Tutor
q (LL LL)
z (Lx xL)Left (Previous slide)
Ctrl (xL Lx)
Alt (Lx LL)
Escape (xL LL)
Tab (LL Lx)
LL xL Not used yet

See also