<s>
An	O
always-on	O
display	O
(	O
AOD	O
)	O
is	O
a	O
smartphone	B-Application
feature	O
that	O
has	O
the	O
device	O
continue	O
to	O
show	O
limited	O
information	O
while	O
the	O
phone	O
is	O
asleep	O
.	O
</s>
<s>
It	O
is	O
widely	O
available	O
on	O
Android	B-Application
handsets	O
,	O
and	O
is	O
available	O
on	O
Apple	O
iPhones	B-Device
since	O
the	O
iPhone	B-Operating_System
14	I-Operating_System
Pro	I-Operating_System
.	O
</s>
<s>
On	O
some	O
Android	B-Application
devices	O
,	O
the	O
feature	O
is	O
sometimes	O
called	O
Ambient	O
Display	O
(	O
Google	O
pixel	O
)	O
or	O
Active	O
Display	O
,	O
depending	O
on	O
its	O
implementation	O
and	O
behavior	O
.	O
</s>
<s>
Depending	O
on	O
the	O
phone	O
's	O
design	O
,	O
it	O
may	O
be	O
a	O
replacement	O
or	O
complementary	O
to	O
another	O
feature	O
,	O
such	O
as	O
the	O
notification	B-Application
LED	I-Application
.	O
</s>
<s>
An	O
Always	B-Application
On	I-Application
Display	I-Application
may	O
display	O
a	O
set	O
of	O
recent	O
push	B-General_Concept
notifications	I-General_Concept
in	O
place	O
of	O
a	O
notification	O
tone	O
or	O
LED	O
signal	O
,	O
as	O
well	O
as	O
information	O
such	O
as	O
the	O
time	O
,	O
date	O
,	O
and	O
battery	O
status	O
of	O
the	O
device	O
;	O
they	O
often	O
may	O
also	O
be	O
configured	O
to	O
also	O
show	O
various	O
types	O
of	O
notifications	O
as	O
they	O
arrive	O
,	O
or	O
screensavers	B-General_Concept
.	O
</s>
<s>
Some	O
phones	O
would	O
have	O
the	O
screen	O
off	O
until	O
new	O
notifications	O
arrive	O
whereupon	O
the	O
display	O
would	O
either	O
be	O
active	O
for	O
a	O
few	O
seconds	O
or	O
remain	O
on	O
until	O
the	O
user	O
interacts	O
with	O
the	O
device	O
to	O
read	O
or	O
dismiss	O
the	O
notification	O
(	O
essentially	O
having	O
the	O
entire	O
screen	O
serve	O
as	O
a	O
larger	O
notification	B-Application
LED	I-Application
)	O
;	O
others	O
instead	O
have	O
the	O
phone	O
screen	O
activate	O
when	O
it	O
detects	O
input	O
,	O
such	O
as	O
being	O
picked	O
up	O
or	O
the	O
screen	O
interacted	O
with	O
.	O
</s>
<s>
These	O
versions	O
are	O
often	O
called	O
ambient	O
displays	O
,	O
in	O
contrast	B-Device
to	O
"	O
true	O
"	O
always-on	O
displays	O
,	O
where	O
at	O
least	O
part	O
of	O
the	O
screen	O
remains	O
on	O
at	O
all	O
times	O
.	O
</s>
<s>
This	O
technology	O
was	O
first	O
introduced	O
by	O
Nokia	O
in	O
on	O
the	O
Nokia	B-Language
N70	I-Language
and	O
Nokia	O
6303	O
(	O
on	O
TFT	B-Device
display	I-Device
in	O
2008	O
)	O
,	O
and	O
more	O
widely	O
adopted	O
with	O
its	O
next	O
generation	O
AMOLED	B-Algorithm
Symbian	O
phones	O
in	O
2010	O
(	O
the	O
Nokia	O
N8	O
,	O
C7	O
,	O
C6-01	O
and	O
E7	O
)	O
.	O
</s>
<s>
Later	O
functionality	O
was	O
updated	O
with	O
Nokia	O
Sleeping	O
Screen	O
app	O
for	O
last	O
generation	O
of	O
Symbian	O
smartphones	B-Application
(	O
Nokia	O
808	O
and	O
other	O
)	O
with	O
features	O
like	O
custom	O
standby	O
screen	O
from	O
any	O
image	O
,	O
and	O
two	O
themes	O
for	O
notifications	O
design	O
.	O
</s>
<s>
It	O
became	O
a	O
standard	O
feature	O
on	O
most	O
Nokia	B-Device
Lumia	I-Device
Windows	O
Phones	O
in	O
2013	O
,	O
paired	O
with	O
the	O
Nokia	B-Device
Glance	I-Device
Screen	O
app	O
.	O
</s>
<s>
The	O
feature	O
has	O
since	O
become	O
more	O
widely	O
available	O
on	O
Android	B-Application
handsets	O
.	O
</s>
<s>
Apple	O
has	O
the	O
feature	O
since	O
Apple	B-Device
Watch	I-Device
Series	I-Device
5	I-Device
(	O
2019	O
)	O
and	O
on	O
iPhone	B-Operating_System
14	I-Operating_System
Pro	I-Operating_System
in	O
2022	O
.	O
</s>
<s>
The	O
Always	B-Application
On	I-Application
Display	I-Application
feature	O
does	O
consume	O
energy	O
,	O
although	O
the	O
Samsung	B-Application
Galaxy	I-Application
S7	I-Application
series	O
phones	O
,	O
and	O
later	O
phones	O
that	O
made	O
the	O
feature	O
popular	O
are	O
built	O
with	O
AMOLED	B-Algorithm
screens	O
that	O
turn	O
off	O
black	O
pixels	O
.	O
</s>
<s>
On	O
today	O
's	O
AMOLED	B-Algorithm
phone	O
displays	O
,	O
it	O
is	O
true	O
that	O
only	O
a	O
few	O
pixels	O
may	O
need	O
to	O
be	O
turned	O
on	O
but	O
they	O
do	O
need	O
to	O
be	O
moved	O
to	O
prevent	O
pixel	B-General_Concept
burn	I-General_Concept
in	I-General_Concept
.	O
</s>
<s>
On	O
LCD	O
displays	O
,	O
the	O
backlight	O
has	O
to	O
be	O
turned	O
on	O
,	O
even	O
if	O
only	O
a	O
part	O
of	O
the	O
screen	O
is	O
showing	O
information	O
,	O
so	O
this	O
feature	O
consumes	O
a	O
significant	O
amount	O
of	O
power	O
compared	O
to	O
a	O
notification	B-Application
LED	I-Application
.	O
</s>
<s>
Some	O
LCD	O
displays	O
use	O
Transflective	B-General_Concept
LCD	I-General_Concept
.	O
</s>
<s>
Some	O
smartwatches	B-Application
such	O
as	O
the	O
Pebble	B-Device
Smartwatch	I-Device
and	O
the	O
Amazfit	O
Stratos	O
also	O
use	O
this	O
technology	O
.	O
</s>
<s>
when	O
exposed	O
to	O
daylight	O
)	O
the	O
display	O
acts	O
mainly	O
as	O
a	O
reflective	O
display	O
with	O
the	O
contrast	B-Device
being	O
constant	O
with	O
illuminance	O
.	O
</s>
<s>
Typically	O
,	O
an	O
ambient	O
display	O
solution	O
which	O
turns	O
on	O
the	O
screen	O
only	O
when	O
notifications	O
are	O
present	O
,	O
remains	O
on	O
,	O
but	O
turns	O
off	O
when	O
they	O
are	O
dismissed	O
will	O
consume	O
the	O
least	O
amount	O
of	O
battery	O
power	O
while	O
still	O
drawing	O
the	O
user	O
's	O
attention	O
when	O
required	O
,	O
in	O
contrast	B-Device
to	O
an	O
Always-on	O
Display	O
which	O
will	O
keep	O
the	O
screen	O
on	O
,	O
all	O
of	O
the	O
time	O
,	O
to	O
show	O
some	O
information	O
,	O
even	O
if	O
notifications	O
may	O
not	O
be	O
present	O
.	O
</s>
<s>
In	O
some	O
phones	O
,	O
the	O
Always	O
On	O
Display/Ambient	O
Display	O
feature	O
can	O
be	O
toggled	O
on	O
a	O
schedule	O
,	O
such	O
as	O
during	O
nighttime	O
,	O
or	O
when	O
the	O
proximity	B-Device
sensor	I-Device
detects	O
that	O
the	O
device	O
is	O
in	O
a	O
pocket	O
.	O
</s>
