<s>
The	O
fourth	O
generation	O
iPod	B-Operating_System
Touch	I-Operating_System
(	O
marketed	O
as	O
"	O
the	O
new	O
iPod	B-Operating_System
touch	I-Operating_System
"	O
,	O
and	O
colloquially	O
known	O
as	O
the	B-Device
iPod	B-Operating_System
Touch	I-Operating_System
4G	O
,	O
iPod	B-Operating_System
Touch	I-Operating_System
4	I-Operating_System
,	O
or	O
iPod	B-Operating_System
4	I-Operating_System
)	O
is	O
a	O
multi-touch	B-Application
mobile	B-Application
device	I-Application
designed	O
and	O
marketed	O
by	O
Apple	O
Inc	O
.	O
with	O
a	O
touchscreen-based	B-Device
user	B-Application
interface	I-Application
.	O
</s>
<s>
The	O
successor	O
to	O
the	O
3rd-generation	B-Operating_System
iPod	I-Operating_System
Touch	I-Operating_System
,	O
it	O
was	O
unveiled	O
at	O
Apple	O
's	O
media	O
event	O
on	O
September	O
1	O
,	O
2010	O
,	O
and	O
was	O
released	O
on	O
September	O
12	O
,	O
2010	O
.	O
</s>
<s>
The	O
fourth-generation	O
iPod	B-Operating_System
Touch	I-Operating_System
was	O
the	O
first	O
iPod	B-Device
to	O
offer	O
front	O
and	O
rear	O
facing	O
cameras	O
.	O
</s>
<s>
It	O
is	O
a	O
slimmer	O
,	O
lighter	O
model	O
than	O
its	O
predecessors	O
and	O
the	O
iPhone	B-Operating_System
4	I-Operating_System
,	O
and	O
introduces	O
a	O
Retina	B-Operating_System
Display	I-Operating_System
.	O
</s>
<s>
Other	O
improvements	O
include	O
support	O
for	O
recording	O
720p	O
video	O
via	O
the	O
rear	O
camera	O
,	O
Apple	O
's	O
A4	O
chip	O
(	O
the	O
same	O
chip	O
used	O
in	O
the	O
iPad	B-Operating_System
(	O
1st	O
generation	O
)	O
,	O
and	O
iPhone	B-Operating_System
4	I-Operating_System
)	O
.	O
</s>
<s>
The	O
fourth-generation	O
iPod	B-Operating_System
Touch	I-Operating_System
was	O
initially	O
released	O
with	O
a	O
single	O
color	O
option	O
.	O
</s>
<s>
On	O
October	O
12	O
,	O
2011	O
,	O
with	O
the	O
release	O
of	O
the	O
iPhone	B-Operating_System
4S	I-Operating_System
,	O
the	O
white-colored	O
version	O
was	O
added	O
and	O
the	O
stainless	O
steel	O
back	O
remained	O
unchanged	O
.	O
</s>
<s>
It	O
was	O
the	O
last	O
iPod	B-Operating_System
Touch	I-Operating_System
to	O
have	O
this	O
customization	O
option	O
,	O
because	O
it	O
was	O
removed	O
with	O
the	O
release	O
of	O
the	O
fifth-generation	B-Operating_System
iPod	I-Operating_System
Touch	I-Operating_System
,	O
which	O
removed	O
the	O
front	O
color	O
options	O
in	O
favor	O
of	O
changing	O
the	O
faceplate	O
color	O
depending	O
on	O
the	O
back	O
color	O
of	O
the	O
device	O
.	O
</s>
<s>
On	O
October	O
11	O
,	O
2012	O
,	O
Apple	O
discontinued	O
the	O
8	O
GB	O
and	O
64	O
GB	O
models	O
with	O
the	O
release	O
of	O
the	O
32	O
and	O
64	O
GB	O
models	O
of	O
the	O
fifth-generation	B-Operating_System
iPod	I-Operating_System
Touch	I-Operating_System
.	O
</s>
<s>
The	B-Device
iPod	I-Device
Touch	O
(	O
4th	O
generation	O
)	O
was	O
officially	O
discontinued	O
by	O
Apple	O
on	O
May	O
30	O
,	O
2013	O
,	O
with	O
the	O
release	O
of	O
a	O
16	O
GB	O
version	O
of	O
its	O
successor	O
,	O
the	B-Device
iPod	I-Device
Touch	O
5	O
.	O
</s>
<s>
It	O
is	O
also	O
the	O
last	O
of	O
the	B-Device
iPod	B-Operating_System
Touch	I-Operating_System
players	O
released	O
to	O
use	O
the	O
30-pin	O
dock	O
connector	O
,	O
which	O
was	O
substituted	O
with	O
the	O
Lightning	B-Architecture
connector	I-Architecture
starting	O
with	O
the	O
5th	O
generation	O
of	O
iPod	B-Operating_System
Touch	I-Operating_System
devices	O
.	O
</s>
<s>
It	O
fully	O
supports	O
iOS	B-Operating_System
4	I-Operating_System
,	O
and	O
iOS	B-Operating_System
5	I-Operating_System
,	O
but	O
has	O
limited	O
support	O
for	O
iOS	B-Operating_System
6	I-Operating_System
.	O
</s>
<s>
Unlike	O
the	O
iPhone	B-Operating_System
4	I-Operating_System
,	O
it	O
did	O
not	O
support	O
iOS	B-Operating_System
7	I-Operating_System
due	O
to	O
performance	O
issues	O
.	O
</s>
<s>
On	O
November	O
14	O
,	O
2013	O
,	O
Apple	O
issued	O
iOS	O
6.1.5	O
for	O
the	B-Device
iPod	I-Device
touch	O
(	O
4th	O
generation	O
)	O
to	O
fix	O
FaceTime	O
calls	O
failing	O
.	O
</s>
<s>
On	O
February	O
21	O
,	O
2014	O
,	O
Apple	O
issued	O
iOS	O
6.1.6	O
for	O
the	B-Device
iPod	I-Device
touch	O
(	O
4th	O
generation	O
)	O
and	O
iPhone	B-Operating_System
3GS	I-Operating_System
to	O
fix	O
faulty	O
SSL	O
verification	O
.	O
</s>
