<s>
Acer	B-Device
Z520	I-Device
is	O
a	O
high-end	O
smartphone	B-Application
made	O
by	O
Acer	O
Inc	O
.	O
much	O
slimmer	O
than	O
IPhone	B-Operating_System
4	I-Operating_System
.	O
</s>
<s>
Its	O
hardware	O
was	O
1.3GHz	O
Mediatek	B-Architecture
MT6582	O
quad	O
core	O
,	O
2.3GHz	O
dual-core	O
NVIDIA	B-Operating_System
Tegra	I-Operating_System
Denver	O
or	O
1.4GHz	O
Qualcomm	B-Architecture
Snapdragon	I-Architecture
320	O
and	O
can	O
underclock	O
to	O
1.2GHz	O
(	O
for	O
MTK	O
Only	O
)	O
and	O
the	O
graphics	O
was	O
ARM	B-General_Concept
Mali-400	I-General_Concept
,	O
ULP	B-Application
GeForce	I-Application
with	O
tesselation	O
,	O
instant	O
rendering	O
and	O
vertex	O
array	O
object	O
from	O
OpenGL	O
ES	O
3.0	O
,	O
or	O
else	O
Adreno	B-General_Concept
320	O
.	O
</s>
<s>
At	O
2014	O
,	O
it	O
would	O
be	O
now	O
update	O
to	O
4.4.4	O
Kitkat	O
for	O
liquid	O
variants	O
and	O
uses	O
1.6GHz	O
64-bit	B-Device
Quad-Core	O
Snapdragon	B-Architecture
S4	O
play	O
with	O
Adreno	B-General_Concept
320	O
and	O
original	O
variant	O
update	O
to	O
5.0	O
Lollipop	O
.	O
</s>
<s>
Acer	B-Device
Z520	I-Device
uses	O
2G	O
,	O
3G	B-Architecture
,	O
and	O
4G-HSPA	B-Architecture
+	I-Architecture
.	O
</s>
<s>
The	O
top	O
speed	O
in	O
2G	O
was	O
1024kbit/s	O
downlink	O
and	O
768kbit/s	O
uplink	B-Application
.	O
</s>
<s>
In	O
3G	B-Architecture
,	O
the	O
top	O
speed	O
was	O
14.2MB/s	O
downlink	O
and	O
7.6MB/s	O
uplink	B-Application
.	O
</s>
<s>
In	O
4G-HSPA	B-Architecture
+	I-Architecture
,	O
the	O
top	O
speed	O
was	O
26.4MB/s	O
downlink	O
and	O
13.2MB/s	O
uplink	B-Application
.	O
</s>
<s>
Bluetooth	O
hardware	O
is	O
Mediatek	B-Architecture
which	O
supports	O
up	O
to	O
50	O
meters	O
and	O
WIFI	O
is	O
Ralink	O
which	O
also	O
supports	O
up	O
to	O
120	O
meters	O
.	O
</s>
