<s>
Fieldrunners	B-Device
is	O
a	O
tower	B-Application
defense	I-Application
video	O
game	O
developed	O
for	O
several	O
platforms	O
.	O
</s>
<s>
Originally	O
released	O
on	O
1	O
October	O
2008	O
as	O
an	O
exclusive	O
iOS	B-Application
title	O
,	O
the	O
game	O
was	O
later	O
ported	O
to	O
Nintendo	B-Device
DSi	I-Device
,	O
PlayStation	B-Operating_System
Portable	I-Operating_System
,	O
PlayStation	B-Operating_System
3	I-Operating_System
,	O
and	O
mobile	O
phones	O
.	O
</s>
<s>
It	O
was	O
released	O
on	O
the	O
Android	B-Application
platform	I-Application
in	O
July	O
2011	O
,	O
on	O
the	O
Amazon	O
Appstore	B-Application
and	O
Android	B-Application
Market	I-Application
,	O
then	O
on	O
25	O
October	O
,	O
where	O
it	O
was	O
ported	O
to	O
HTML5	O
by	O
Gradient	O
Studios	O
and	O
Bocoup	O
and	O
released	O
on	O
the	O
Chrome	B-Application
Web	I-Application
Store	I-Application
with	O
the	O
first	O
level	O
,	O
Grasslands	O
,	O
playable	O
for	O
free	O
.	O
</s>
<s>
Unlike	O
in	O
other	O
tower	B-Application
defense	I-Application
games	I-Application
,	O
turrets	O
can	O
be	O
placed	O
anywhere	O
and	O
the	O
enemies	O
will	O
go	O
around	O
them	O
,	O
forcing	O
them	O
to	O
walk	O
along	O
any	O
path	O
the	O
player	O
makes	O
.	O
</s>
<s>
Fieldrunners	B-Device
offers	O
three	O
types	O
of	O
gameplay	O
:	O
Classic	O
,	O
Extended	O
and	O
Endless	O
.	O
</s>
<s>
Fieldrunners	B-Device
has	O
received	O
generally	O
positive	O
reviews	O
,	O
with	O
the	O
PSP	B-Operating_System
version	O
scoring	O
81%	O
at	O
the	O
review	O
aggregate	O
website	O
Metacritic	O
.	O
</s>
<s>
was	O
highly	O
critical	O
of	O
the	O
PC	B-Device
port	O
,	O
but	O
expressed	O
enjoyment	O
of	O
the	O
mobile	O
releases	O
.	O
</s>
<s>
Of	O
the	O
iPhone	O
version	O
,	O
Stuart	O
Dredge	O
of	O
Pocket	O
Gamer	O
noted	O
its	O
"	O
clever	O
controls	O
and	O
cartoony	O
visuals	O
"	O
,	O
calling	O
it	O
"	O
the	O
best	O
Tower	B-Application
Defense	I-Application
game	I-Application
on	O
iPhone	O
so	O
far	O
"	O
.	O
</s>
<s>
The	O
PSP	B-Operating_System
version	O
of	O
Fieldrunners	B-Device
scored	O
a	O
high	O
81/100	O
on	O
Metacritic	O
.	O
</s>
<s>
Reviews	O
for	O
the	O
iPad	B-Device
Fieldrunners	B-Device
HD	O
version	O
have	O
been	O
positive	O
.	O
</s>
