<s>
Koronavilkku	B-Application
(	O
Swedish	O
:	O
Coronablinkern	O
,	O
English	O
:	O
Corona	O
signal	O
)	O
is	O
a	O
COVID-19	B-Application
app	I-Application
and	O
a	O
digital	B-Protocol
contact	I-Protocol
tracing	I-Protocol
mobile	B-Application
app	I-Application
developed	O
by	O
the	O
Finnish	O
Institute	O
for	O
Health	O
and	O
Welfare	O
to	O
inform	O
citizens	O
of	O
when	O
they	O
may	O
have	O
been	O
exposed	O
to	O
the	O
COVID-19	O
virus	O
.	O
</s>
<s>
The	O
free	O
app	O
became	O
available	O
for	O
download	O
on	O
Google	B-Application
Play	I-Application
and	O
App	B-Application
Store	I-Application
on	O
August	O
31	O
,	O
2020	O
,	O
and	O
was	O
downloaded	O
one	O
million	O
times	O
in	O
the	O
first	O
day	O
.	O
</s>
