<s>
Gesture-enhanced	B-Application
single-touch	I-Application
,	O
also	O
known	O
as	O
"	O
dual	O
control	O
"	O
,	O
"	O
gesture	B-Application
touch	I-Application
"	O
,	O
and	O
often	O
"	O
dual-touch	O
"	O
,	O
describes	O
the	O
ability	O
of	O
a	O
touchscreen	B-Device
to	O
register	O
certain	O
two-finger	O
gestures	B-General_Concept
,	O
despite	O
lacking	O
hardware	O
that	O
would	O
allow	O
it	O
to	O
fully	O
register	O
all	O
two-finger	O
movements	O
.	O
</s>
<s>
A	O
very	O
common	O
application	O
of	O
gesture-enhanced	B-Application
single-touch	I-Application
technology	O
is	O
the	O
pinch-to-zoom	B-Application
gesture	O
,	O
which	O
allows	O
the	O
user	O
to	O
zoom	O
in	O
or	O
out	O
by	O
moving	O
two	O
fingers	O
farther	O
apart	O
or	O
closer	O
together	O
while	O
touching	O
the	O
display	O
.	O
</s>
<s>
An	O
important	O
technical	O
reason	O
for	O
the	O
limitation	O
to	O
gesture-enhanced	B-Application
single-touch	I-Application
instead	O
of	O
allowing	O
dual-touch	O
or	O
multi-touch	B-Application
is	O
the	O
type	O
of	O
sensor	O
hardware	O
in	O
the	O
display	O
.	O
</s>
<s>
Many	O
touchscreen	B-Device
technologies	O
obtain	O
two	O
independent	O
measurements	O
per	O
touch	O
to	O
acquire	O
a	O
2-dimensional	O
position	O
.	O
</s>
