<s>
Dropbox	B-Application
is	O
a	O
file	B-Application
hosting	I-Application
service	I-Application
operated	O
by	O
the	O
American	O
company	O
Dropbox	B-Application
,	O
Inc.	O
,	O
headquartered	O
in	O
San	O
Francisco	O
,	O
California	O
,	O
U.S.	O
that	O
offers	O
cloud	O
storage	O
,	O
file	B-Application
synchronization	I-Application
,	O
personal	B-General_Concept
cloud	I-General_Concept
,	O
and	O
client	B-Protocol
software	I-Protocol
.	O
</s>
<s>
Dropbox	B-Application
was	O
founded	O
in	O
2007	O
by	O
MIT	O
students	O
Drew	O
Houston	O
and	O
Arash	O
Ferdowsi	O
as	O
a	O
startup	O
company	O
,	O
with	O
initial	O
funding	O
from	O
seed	O
accelerator	O
Y	O
Combinator	O
.	O
</s>
<s>
Dropbox	B-Application
has	O
experienced	O
criticism	O
and	O
generated	O
controversy	O
for	O
issues	O
including	O
security	O
breaches	O
and	O
privacy	O
concerns	O
.	O
</s>
<s>
Dropbox	B-Application
has	O
been	O
blocked	O
in	O
China	O
since	O
2014	O
.	O
</s>
<s>
Dropbox	B-Application
brings	O
files	O
together	O
in	O
one	O
central	O
place	O
by	O
creating	O
a	O
special	O
folder	O
on	O
the	O
user	O
's	O
computer	O
.	O
</s>
<s>
The	O
contents	O
of	O
these	O
folders	O
are	O
synchronized	O
to	O
Dropbox	B-Application
's	O
servers	O
and	O
to	O
other	O
computers	O
and	O
devices	O
where	O
the	O
user	O
has	O
installed	O
Dropbox	B-Application
,	O
keeping	O
the	O
same	O
files	O
up-to-date	O
on	O
all	O
devices	O
.	O
</s>
<s>
Dropbox	B-Application
uses	O
a	O
freemium	O
business	O
model	O
,	O
where	O
users	O
are	O
offered	O
a	O
free	O
account	O
with	O
set	O
storage	O
size	O
,	O
with	O
paid	O
subscriptions	O
available	O
that	O
offer	O
more	O
capacity	O
and	O
additional	O
features	O
.	O
</s>
<s>
Dropbox	B-Application
Basic	O
users	O
are	O
given	O
two	O
gigabytes	O
of	O
free	O
storage	O
space	O
.	O
</s>
<s>
Dropbox	B-Application
offers	O
computer	O
apps	O
for	O
Microsoft	B-Application
Windows	I-Application
,	O
Apple	O
macOS	B-Application
,	O
and	O
Linux	B-Application
computers	O
,	O
and	O
mobile	O
apps	O
for	O
iOS	B-Application
,	O
Android	B-Application
,	O
and	O
Windows	B-Protocol
Phone	I-Protocol
smartphones	B-Application
and	O
tablets	B-Device
.	O
</s>
<s>
In	O
March	O
2013	O
,	O
the	O
company	O
acquired	O
Mailbox	B-Protocol
,	O
a	O
popular	O
email	O
app	O
,	O
and	O
in	O
April	O
2014	O
,	O
the	O
company	O
introduced	O
Dropbox	B-Algorithm
Carousel	I-Algorithm
,	O
a	O
photo	O
and	O
video	O
gallery	O
app	O
.	O
</s>
<s>
Both	O
Mailbox	B-Protocol
and	O
Carousel	B-Algorithm
were	O
shut	O
down	O
in	O
December	O
2015	O
,	O
with	O
key	O
features	O
from	O
both	O
apps	O
implemented	O
into	O
the	O
regular	O
Dropbox	B-Application
service	O
.	O
</s>
<s>
In	O
October	O
2015	O
,	O
it	O
officially	O
announced	O
Dropbox	B-Application
Paper	I-Application
,	O
its	O
collaborative	O
document	O
editor	O
.	O
</s>
<s>
Dropbox	B-Application
founder	O
Drew	O
Houston	O
conceived	O
the	O
Dropbox	B-Application
concept	O
after	O
repeatedly	O
forgetting	O
his	O
USB	B-Protocol
flash	O
drive	O
while	O
he	O
was	O
a	O
student	O
at	O
MIT	O
.	O
</s>
<s>
Houston	O
founded	O
Evenflow	O
,	O
Inc	O
.	O
in	O
May	O
2007	O
as	O
the	O
company	O
behind	O
Dropbox	B-Application
,	O
and	O
shortly	O
thereafter	O
secured	O
seed	O
funding	O
from	O
Y	O
Combinator	O
.	O
</s>
<s>
Dropbox	B-Application
was	O
officially	O
launched	O
at	O
2008	O
's	O
TechCrunch	O
Disrupt	O
,	O
an	O
annual	O
technology	O
conference	O
.	O
</s>
<s>
Owing	O
to	O
trademark	O
disputes	O
between	O
Proxy	O
,	O
Inc	O
.	O
and	O
Evenflow	O
,	O
Dropbox	B-Application
's	O
official	O
domain	O
name	O
was	O
"	O
getdropbox.com	O
 "	O
until	O
October	O
2009	O
,	O
when	O
it	O
acquired	O
its	O
current	O
domain	O
,	O
"	O
dropbox.com	B-Application
 "	O
.	O
</s>
<s>
In	O
October	O
2009	O
,	O
Evenflow	O
,	O
Inc	O
.	O
was	O
renamed	O
Dropbox	B-Application
,	I-Application
Inc	I-Application
.	I-Application
</s>
<s>
In	O
an	O
interview	O
with	O
TechCrunch	O
's	O
"	O
Founder	O
Stories	O
"	O
in	O
October	O
2011	O
,	O
Houston	O
explained	O
that	O
a	O
demo	O
video	O
was	O
released	O
during	O
Dropbox	B-Application
's	O
early	O
days	O
,	O
with	O
one	O
viewer	O
being	O
Arash	O
Ferdowsi	O
.	O
</s>
<s>
Dropbox	B-Application
saw	O
steady	O
user	O
growth	O
after	O
its	O
inception	O
.	O
</s>
<s>
In	O
July	O
2012	O
,	O
Dropbox	B-Application
acquired	O
TapEngage	O
,	O
a	O
startup	O
that	O
"	O
enables	O
advertisers	O
and	O
publishers	O
to	O
collaborate	O
on	O
tablet-optimized	O
advertising	O
"	O
.	O
</s>
<s>
The	O
following	O
December	O
,	O
Dropbox	B-Application
acquired	O
two	O
companies	O
;	O
Audiogalaxy	O
,	O
a	O
startup	O
"	O
allowing	O
users	O
to	O
store	O
their	O
music	O
files	O
and	O
playlists	O
in	O
the	O
cloud	O
then	O
stream	O
them	O
to	O
any	O
device	O
"	O
,	O
and	O
Snapjoy	O
,	O
a	O
company	O
that	O
allowed	O
users	O
to	O
"	O
aggregate	O
,	O
archive	O
and	O
view	O
all	O
of	O
their	O
digital	O
photos	O
from	O
their	O
cameras	B-Device
,	O
phones	O
and	O
popular	O
apps	O
like	O
Flickr	B-Algorithm
,	O
Instagram	B-Application
and	O
Picasa	B-Application
,	O
and	O
then	O
view	O
them	O
online	O
or	O
via	O
an	O
iOS	B-Application
app	O
"	O
.	O
</s>
<s>
In	O
July	O
2013	O
,	O
Dropbox	B-Application
acquired	O
Endorse	O
,	O
a	O
"	O
mobile	O
coupon	O
startup	O
"	O
.	O
</s>
<s>
In	O
May	O
2014	O
,	O
Dropbox	B-Application
acquired	O
Bubbli	O
,	O
a	O
startup	O
that	O
has	O
"	O
built	O
some	O
innovative	O
ways	O
of	O
incorporating	O
3D	O
technology	O
into	O
2D	O
views	O
,	O
and	O
packaging	O
it	O
in	O
a	O
mobile	O
app	O
"	O
.	O
</s>
<s>
In	O
January	O
2015	O
,	O
Dropbox	B-Application
acquired	O
CloudOn	O
,	O
a	O
company	O
that	O
provided	O
mobile	O
applications	O
for	O
document	O
editing	O
and	O
creation	O
.	O
</s>
<s>
At	O
the	O
same	O
time	O
,	O
Dropbox	B-Application
told	O
TechCrunch	O
that	O
CloudOn	O
's	O
base	O
in	O
Herzliya	O
would	O
become	O
the	O
first	O
Dropbox	B-Application
office	O
in	O
Israel	O
.	O
</s>
<s>
In	O
July	O
,	O
Dropbox	B-Application
acquired	O
Clementine	O
,	O
an	O
enterprise	O
communication	O
service	O
.	O
</s>
<s>
In	O
April	O
2014	O
,	O
Dropbox	B-Application
acquired	O
photo-sharing	O
company	O
Loom	O
(	O
which	O
would	O
be	O
shut	O
down	O
and	O
integrated	O
with	O
the	O
then-recently	O
announced	O
Carousel	B-Algorithm
)	O
,	O
and	O
document-sharing	O
startup	O
Hackpad	B-Application
.	O
</s>
<s>
Dropbox	B-Application
later	O
announced	O
in	O
April	O
2017	O
that	O
Hackpad	B-Application
would	O
be	O
shut	O
down	O
on	O
July	O
19	O
,	O
with	O
all	O
notes	O
being	O
migrated	O
to	O
Dropbox	B-Application
Paper	I-Application
.	O
</s>
<s>
In	O
January	O
2019	O
,	O
Dropbox	B-Application
acquired	O
e-signature	O
company	O
HelloSign	O
.	O
</s>
<s>
The	O
acquisition	O
was	O
reported	O
to	O
be	O
Dropbox	B-Application
's	O
largest	O
to	O
date	O
,	O
at	O
a	O
reported	O
$230	O
million	O
.	O
</s>
<s>
In	O
March	O
2021	O
,	O
Dropbox	B-Application
announced	O
the	O
acquisition	O
of	O
DocSend	O
.	O
</s>
<s>
At	O
the	O
start	O
of	O
the	O
Covid-19	O
pandemic	O
in	O
2020	O
,	O
Dropbox	B-Application
was	O
one	O
of	O
the	O
first	O
companies	O
to	O
shift	O
to	O
a	O
remote	O
workforce	O
.	O
</s>
<s>
In	O
January	O
2021	O
,	O
Dropbox	B-Application
CEO	O
Houston	O
announced	O
the	O
layoff	O
of	O
315	O
employees	O
,	O
which	O
is	O
approximately	O
11	O
percent	O
of	O
the	O
current	O
workforce	O
.	O
</s>
<s>
Dropbox	B-Application
has	O
computer	O
apps	O
for	O
Microsoft	B-Application
Windows	I-Application
,	O
Apple	O
macOS	B-Application
,	O
and	O
Linux	B-Application
computers	O
,	O
and	O
mobile	O
apps	O
for	O
iOS	B-Application
,	O
Android	B-Application
,	O
and	O
Windows	B-Protocol
Phone	I-Protocol
smartphones	B-Application
and	O
tablets	B-Device
.	O
</s>
<s>
It	O
also	O
offers	O
a	O
website	B-Application
interface	I-Application
.	O
</s>
<s>
As	O
part	O
of	O
its	O
partnership	O
with	O
Microsoft	O
,	O
Dropbox	B-Application
announced	O
a	O
universal	B-Device
Windows	I-Device
10	I-Device
app	I-Device
in	O
January	O
2016	O
.	O
</s>
<s>
Dropbox	B-Application
's	O
apps	O
offer	O
an	O
automatic	O
photo	O
uploading	O
feature	O
,	O
allowing	O
users	O
to	O
automatically	O
upload	O
photos	O
or	O
videos	O
from	O
cameras	B-Device
,	O
tablets	B-Device
,	O
SD	B-Device
cards	I-Device
,	O
or	O
smartphones	B-Application
to	O
a	O
dedicated	O
"	O
Camera	O
Uploads	O
"	O
folder	O
in	O
their	O
Dropbox	B-Application
.	O
</s>
<s>
In	O
July	O
2014	O
,	O
Dropbox	B-Application
introduced	O
"	O
streaming	O
sync	O
"	O
for	O
its	O
computer	O
apps	O
.	O
</s>
<s>
In	O
August	O
2015	O
,	O
Dropbox	B-Application
announced	O
the	O
availability	O
of	O
"	O
Universal	O
2nd	O
Factor	O
"	O
USB	B-Protocol
security	O
keys	O
,	O
providing	O
two-factor	O
authentication	O
for	O
logging	O
into	O
its	O
services	O
.	O
</s>
<s>
The	O
Dropbox	B-Application
app	O
for	O
Windows	B-Application
requires	O
:	O
</s>
<s>
The	O
Dropbox	B-Application
app	O
for	O
Windows	B-Application
in	O
S	O
mode	O
requires	O
:	O
</s>
<s>
The	O
Dropbox	B-Application
app	O
for	O
Linux	B-Application
requires	O
:	O
</s>
<s>
A	O
Linux	B-Application
computer	O
formatted	O
with	O
any	O
of	O
the	O
following	O
file	O
systems	O
:	O
</s>
<s>
The	O
Dropbox	B-Application
app	O
for	O
iPhone	B-Device
and	O
iPad	B-Device
requires	O
:	O
</s>
<s>
The	O
Dropbox	B-Application
app	O
for	O
Mac	O
requires	O
:	O
</s>
<s>
The	O
Dropbox	B-Application
app	O
for	O
Android	B-Application
requires	O
:	O
</s>
<s>
Dropbox	B-Application
received	O
initial	O
funding	O
from	O
seed	O
accelerator	O
Y	O
Combinator	O
.	O
</s>
<s>
Dropbox	B-Application
also	O
raised	O
US	O
$1.2	O
million	O
in	O
Series	O
A	O
funding	O
from	O
Sequoia	O
Capital	O
in	O
2007	O
,	O
that	O
"	O
along	O
with	O
interest	O
(	O
on	O
that	O
amount	O
)	O
converted	O
to	O
equity	O
as	O
part	O
of	O
the	O
Series	O
A	O
investment	O
,	O
which	O
included	O
a	O
fresh	O
slug	O
of	O
US$6	O
million	O
"	O
,	O
bringing	O
the	O
total	O
amount	O
to	O
US	O
$7.25	O
million	O
,	O
with	O
the	O
round	O
closed	O
in	O
2008	O
and	O
documents	O
filed	O
in	O
2009	O
.	O
</s>
<s>
TechCrunch	O
reported	O
in	O
July	O
2011	O
that	O
Dropbox	B-Application
had	O
been	O
looking	O
to	O
raise	O
between	O
US$200	O
and	O
US$300	O
million	O
,	O
and	O
had	O
a	O
valuation	O
"	O
to	O
end	O
up	O
in	O
the	O
$5	O
billion	O
to	O
$10	O
billion	O
range	O
.	O
</s>
<s>
As	O
noted	O
in	O
a	O
Forbes	O
article	O
,	O
Dropbox	B-Application
had	O
"	O
revenue	O
on	O
track	O
to	O
hit	O
$240	O
million	O
in	O
2011	O
"	O
.	O
</s>
<s>
In	O
April	O
2012	O
,	O
Dropbox	B-Application
announced	O
that	O
Bono	O
and	O
The	O
Edge	O
,	O
two	O
members	O
of	O
the	O
Irish	O
rock	O
band	O
U2	O
,	O
were	O
individual	O
investors	O
in	O
the	O
company	O
.	O
</s>
<s>
In	O
2014	O
Dropbox	B-Application
raised	O
financing	O
from	O
BlackRock	O
Inc	O
.	O
and	O
others	O
that	O
values	O
the	O
company	O
at	O
$10	O
billion	O
.	O
</s>
<s>
In	O
March	O
2017	O
,	O
Bloomberg	O
reported	O
that	O
Dropbox	B-Application
had	O
secured	O
a	O
US$600million	O
credit	O
line	O
,	O
with	O
the	O
company	O
expected	O
to	O
file	O
for	O
its	O
initial	O
public	O
offering	O
(	O
IPO	O
)	O
"	O
as	O
soon	O
as	O
this	O
year	O
"	O
.	O
</s>
<s>
In	O
February	O
2018	O
,	O
Dropbox	B-Application
filed	O
an	O
IPO	O
to	O
be	O
listed	O
on	O
the	O
Nasdaq	O
.	O
</s>
<s>
Dropbox	B-Application
's	O
stock	O
rose	O
42	O
percent	O
to	O
$29.89	O
in	O
its	O
first	O
day	O
of	O
trading	O
on	O
March	O
23	O
,	O
2018	O
.	O
</s>
<s>
As	O
of	O
February	O
2021	O
,	O
Dropbox	B-Application
has	O
been	O
profitable	O
in	O
the	O
last	O
three	O
quarters	O
,	O
whilst	O
also	O
having	O
no	O
debt	O
.	O
</s>
<s>
Dropbox	B-Application
uses	O
a	O
freemium	O
business	O
model	O
,	O
where	O
users	O
are	O
offered	O
a	O
free	O
account	O
with	O
a	O
set	O
storage	O
size	O
,	O
with	O
paid	O
subscriptions	O
available	O
that	O
offer	O
more	O
capacity	O
and	O
additional	O
features	O
.	O
</s>
<s>
Accordingly	O
,	O
Dropbox	B-Application
's	O
revenue	O
is	O
a	O
product	O
of	O
how	O
many	O
users	O
they	O
can	O
convert	O
to	O
their	O
paid	O
services	O
.	O
</s>
<s>
Dropbox	B-Application
Basic	O
users	O
are	O
given	O
two	O
gigabytes	O
of	O
free	O
storage	O
space	O
.	O
</s>
<s>
Dropbox	B-Application
Basic	O
users	O
can	O
earn	O
up	O
to	O
16gigabytes	O
through	O
the	O
referral	O
program	O
.	O
</s>
<s>
The	O
Dropbox	B-Application
Plus	O
subscription	O
(	O
named	O
Dropbox	B-Application
Pro	O
prior	O
to	O
March	O
2017	O
)	O
gives	O
users	O
2terabytes	O
of	O
storage	O
space	O
,	O
as	O
well	O
as	O
additional	O
features	O
,	O
including	O
:	O
</s>
<s>
Remote	O
wipe	O
:	O
If	O
a	O
device	O
is	O
stolen	O
or	O
lost	O
,	O
users	O
can	O
remotely	O
wipe	O
the	O
Dropbox	B-Application
folder	O
from	O
the	O
device	O
the	O
next	O
time	O
it	O
comes	O
online	O
.	O
</s>
<s>
"	O
Extended	O
Version	O
History	O
"	O
:	O
An	O
available	O
add-on	O
,	O
it	O
makes	O
Dropbox	B-Application
keep	O
deleted	O
and	O
previous	O
versions	O
of	O
files	O
for	O
one	O
year	O
,	O
a	O
significant	O
extension	O
of	O
the	O
default	O
30-day	O
recovery	O
time	O
.	O
</s>
<s>
In	O
November	O
2013	O
,	O
Dropbox	B-Application
announced	O
changes	O
to	O
"	O
Dropbox	B-Application
for	O
Business	O
"	O
that	O
would	O
enable	O
users	O
to	O
connect	O
both	O
their	O
personal	O
Dropbox	B-Application
and	O
their	O
business	O
Dropbox	B-Application
to	O
the	O
same	O
device	O
,	O
with	O
each	O
of	O
the	O
folders	O
being	O
"	O
properly	O
labeled	O
for	O
personal	O
or	O
work	O
,	O
and	O
come	O
with	O
its	O
own	O
password	O
,	O
contacts	O
,	O
settings	O
,	O
and	O
files	O
"	O
.	O
</s>
<s>
Furthermore	O
,	O
Dropbox	B-Application
announced	O
shared	O
audit	O
logs	O
,	O
remote	O
wipe	O
for	O
business	O
administrators	O
,	O
and	O
account	O
transfers	O
,	O
as	O
new	O
features	O
of	O
its	O
Business	O
offering	O
.	O
</s>
<s>
In	O
January	O
2017	O
,	O
Dropbox	B-Application
introduced	O
"	O
Smart	O
Sync	O
"	O
for	O
Business	O
and	O
Enterprise	O
customers	O
,	O
a	O
feature	O
that	O
lets	O
Windows	B-Application
and	O
macOS	B-Application
users	O
see	O
all	O
files	O
in	O
the	O
Dropbox	B-Application
folder	O
,	O
but	O
only	O
download	O
specific	O
files	O
on-demand	O
.	O
</s>
<s>
Similar	O
to	O
Dropbox	B-Application
Basic	O
,	O
Dropbox	B-Application
Plus	O
users	O
can	O
also	O
earn	O
extra	O
space	O
through	O
referrals	O
.	O
</s>
<s>
Dropbox	B-Application
Business	O
is	O
Dropbox	B-Application
's	O
application	O
for	O
corporations	O
,	O
adding	O
more	O
business-centered	O
functionality	O
for	O
teams	O
,	O
including	O
collaboration	O
tools	O
,	O
advanced	O
security	O
and	O
control	O
,	O
unlimited	O
file	O
recovery	O
,	O
user	O
management	O
and	O
granular	O
permissions	O
,	O
and	O
options	O
for	O
unlimited	O
storage	O
.	O
</s>
<s>
For	O
large	O
organizations	O
,	O
Dropbox	B-Application
offers	O
Dropbox	B-Application
Enterprise	O
,	O
the	O
"	O
highest	O
tier	O
"	O
of	O
its	O
product	O
offerings	O
,	O
adding	O
domain	O
management	O
tools	O
,	O
an	O
assigned	O
Dropbox	B-Application
customer	O
support	O
member	O
,	O
and	O
help	O
from	O
"	O
expert	O
advisors	O
"	O
on	O
deployment	O
and	O
user	O
training	O
.	O
</s>
<s>
In	O
July	O
2016	O
,	O
Dropbox	B-Application
announced	O
a	O
new	O
"	O
AdminX	O
"	O
administrator	O
dashboard	O
for	O
Business	O
customers	O
,	O
offering	O
improved	O
control	O
of	O
company	O
files	O
and	O
users	O
.	O
</s>
<s>
In	O
September	O
2012	O
,	O
Facebook	B-Application
and	O
Dropbox	B-Application
integrated	O
to	O
allow	O
users	O
in	O
Facebook	B-Application
Groups	O
to	O
share	O
files	O
using	O
Dropbox	B-Application
.	O
</s>
<s>
In	O
2013	O
,	O
Samsung	B-Application
pre-loaded	O
the	O
Dropbox	B-Application
mobile	O
application	O
on	O
its	O
Android	B-Application
devices	O
and	O
Dropbox	B-Application
provided	O
extra	O
space	O
for	O
users	O
owning	O
Samsung	B-Application
's	O
devices	O
.	O
</s>
<s>
In	O
November	O
2014	O
,	O
Dropbox	B-Application
announced	O
a	O
partnership	O
with	O
Microsoft	O
to	O
integrate	O
Dropbox	B-Application
and	O
Microsoft	B-Application
Office	I-Application
applications	O
on	O
iOS	B-Application
,	O
Android	B-Application
and	O
the	O
applications	O
on	O
the	O
web	O
.	O
</s>
<s>
On	O
July	O
10	O
,	O
2018	O
,	O
Dropbox	B-Application
announced	O
its	O
partnership	O
with	O
Salesforce	B-Application
aiming	O
to	O
improve	O
brand	O
engagement	O
and	O
team	O
productivity	O
.	O
</s>
<s>
The	O
Dropbox	B-Application
software	O
enables	O
users	O
to	O
drop	O
any	O
file	O
into	O
a	O
designated	O
folder	O
.	O
</s>
<s>
The	O
file	O
is	O
then	O
automatically	O
uploaded	O
to	O
Dropbox	B-Application
's	O
cloud-based	O
service	O
and	O
made	O
available	O
to	O
any	O
other	O
of	O
the	O
user	O
's	O
computers	O
and	O
devices	O
that	O
also	O
have	O
the	O
Dropbox	B-Application
software	O
installed	O
,	O
keeping	O
the	O
file	O
up-to-date	O
on	O
all	O
systems	O
.	O
</s>
<s>
When	O
a	O
file	O
in	O
a	O
user	O
's	O
Dropbox	B-Application
folder	O
is	O
changed	O
,	O
Dropbox	B-Application
only	O
uploads	O
the	O
pieces	B-General_Concept
of	I-General_Concept
the	I-General_Concept
file	I-General_Concept
that	O
have	O
been	O
changed	O
,	O
whenever	O
possible	O
.	O
</s>
<s>
For	O
Dropbox	B-Application
Plus	O
users	O
,	O
this	O
recovery	O
time	O
can	O
be	O
extended	O
to	O
one	O
year	O
,	O
by	O
purchasing	O
an	O
"	O
Extended	O
Version	O
History	O
"	O
add-on	O
.	O
</s>
<s>
Dropbox	B-Application
accounts	O
that	O
are	O
not	O
accessed	O
or	O
emails	O
not	O
replied	O
in	O
a	O
year	O
are	O
automatically	O
deleted	O
.	O
</s>
<s>
Dropbox	B-Application
also	O
offers	O
a	O
LAN	B-General_Concept
sync	O
feature	O
,	O
where	O
,	O
instead	O
of	O
receiving	O
information	O
and	O
data	O
from	O
the	O
Dropbox	B-Application
servers	O
,	O
computers	O
on	O
the	O
local	B-General_Concept
network	I-General_Concept
can	O
exchange	O
files	O
directly	O
between	O
each	O
other	O
,	O
potentially	O
significantly	O
improving	O
synchronization	O
speeds	O
.	O
</s>
<s>
LAN	B-General_Concept
Sync	O
discovers	O
other	O
peers	O
on	O
the	O
same	O
network	O
via	O
UDP	B-Language
port	O
17500	O
using	O
a	O
proprietary	B-Application
discovery	O
protocol	O
developed	O
by	O
early	O
Dropbox	B-Application
engineer	O
Paul	O
Bohm	O
in	O
2010	O
.	O
</s>
<s>
Originally	O
,	O
the	O
Dropbox	B-Application
servers	O
and	O
computer	O
apps	O
were	O
written	O
in	O
Python	B-Language
.	O
</s>
<s>
In	O
July	O
2014	O
,	O
Dropbox	B-Application
began	O
migrating	O
its	O
performance-critical	O
backend	O
infrastructure	O
to	O
Go	B-Application
.	O
</s>
<s>
In	O
September	O
2012	O
,	O
Dropbox	B-Application
's	O
website	O
code	O
base	O
was	O
rewritten	O
from	O
JavaScript	B-Language
to	O
CoffeeScript	B-Application
.	O
</s>
<s>
Dropbox	B-Application
originally	O
used	O
Amazon	B-Application
's	O
S3	B-General_Concept
storage	O
system	O
to	O
store	O
user	O
files	O
,	O
but	O
between	O
2014	O
and	O
2016	O
they	O
gradually	O
moved	O
away	O
from	O
Amazon	B-Application
to	O
use	O
their	O
own	O
hardware	O
,	O
referred	O
to	O
as	O
"	O
Magic	O
Pocket	O
"	O
,	O
due	O
to	O
Dropbox	B-Application
's	O
description	O
as	O
"	O
a	O
place	O
where	O
you	O
keep	O
all	O
your	O
stuff	O
,	O
it	O
does	O
n’t	O
get	O
lost	O
,	O
and	O
you	O
can	O
always	O
access	O
it	O
"	O
.	O
</s>
<s>
Dropbox	B-Application
uses	O
SSL	B-Protocol
transfers	O
for	O
synchronization	O
and	O
stores	O
the	O
data	O
via	O
Advanced	B-Algorithm
Encryption	I-Algorithm
Standard	I-Algorithm
(	O
AES	B-Algorithm
)	O
-256	O
encryption	O
.	O
</s>
<s>
The	O
functionality	O
of	O
Dropbox	B-Application
can	O
be	O
integrated	O
into	O
third-party	O
applications	O
through	O
an	O
application	B-Application
programming	I-Application
interface	I-Application
(	O
API	B-Application
)	O
.	O
</s>
<s>
Dropbox	B-Application
prevents	O
sharing	O
of	O
copyrighted	O
data	O
,	O
by	O
checking	O
the	O
hash	B-Algorithm
of	O
files	O
shared	O
in	O
public	O
folders	O
or	O
between	O
users	O
against	O
a	O
blacklist	O
of	O
copyrighted	O
material	O
.	O
</s>
<s>
This	O
only	O
applies	O
to	O
files	O
or	O
folders	O
shared	O
with	O
other	O
users	O
or	O
publicly	O
,	O
and	O
not	O
to	O
files	O
kept	O
in	O
an	O
individual	O
's	O
Dropbox	B-Application
folder	O
that	O
are	O
not	O
shared	O
.	O
</s>
<s>
In	O
March	O
2013	O
,	O
Dropbox	B-Application
acquired	O
Mailbox	B-Protocol
,	O
a	O
popular	O
email	O
app	O
,	O
with	O
Mailbox	B-Protocol
CEO	O
Gentry	O
Underwood	O
saying	O
that	O
"	O
Rather	O
than	O
grow	O
Mailbox	B-Protocol
on	O
our	O
own	O
,	O
we	O
've	O
decided	O
to	O
join	O
forces	O
with	O
Dropbox	B-Application
and	O
build	O
it	O
out	O
together	O
"	O
.	O
</s>
<s>
Under	O
the	O
deal	O
,	O
the	O
developers	O
of	O
Mailbox	B-Protocol
joined	O
Dropbox	B-Application
,	O
but	O
kept	O
Mailbox	B-Protocol
running	O
as	O
a	O
stand-alone	O
app	O
.	O
</s>
<s>
In	O
December	O
2015	O
,	O
Dropbox	B-Application
announced	O
the	O
shut-down	O
of	O
Mailbox	B-Protocol
.	O
</s>
<s>
In	O
April	O
2014	O
,	O
Dropbox	B-Application
introduced	O
Carousel	B-Algorithm
,	O
a	O
photo	O
and	O
video	O
gallery	O
that	O
"	O
combines	O
the	O
photos	O
in	O
your	O
Dropbox	B-Application
with	O
the	O
photos	O
on	O
your	O
phone	O
,	O
and	O
automatically	O
backs	O
up	O
new	O
ones	O
as	O
you	O
take	O
them.	O
"	O
</s>
<s>
Carousel	B-Algorithm
sorted	O
photos	O
by	O
event	O
and	O
date	O
.	O
</s>
<s>
In	O
December	O
2015	O
,	O
Dropbox	B-Application
announced	O
the	O
shut-down	O
of	O
Carousel	B-Algorithm
.	O
</s>
<s>
In	O
a	O
blog	O
post	O
,	O
Drew	O
Houston	O
and	O
Arash	O
Ferdowsi	O
explained	O
that	O
"	O
We	O
'll	O
be	O
taking	O
key	O
features	O
from	O
Carousel	B-Algorithm
back	O
to	O
the	O
place	O
where	O
your	O
photos	O
live	O
-	O
in	O
the	O
Dropbox	B-Application
app.	O
"	O
</s>
<s>
In	O
April	O
2015	O
,	O
Dropbox	B-Application
launched	O
a	O
Dropbox	B-Application
Notes	O
collaborative	O
note-taking	O
service	O
in	O
beta	O
testing	O
phase	O
,	O
prompting	O
speculation	O
if	O
Dropbox	B-Application
was	O
planning	O
to	O
bring	O
out	O
a	O
product	O
to	O
compete	O
with	O
Google	O
Docs	O
.	O
</s>
<s>
TechCrunch	O
noted	O
that	O
Dropbox	B-Application
Notes	O
appeared	O
to	O
be	O
a	O
new	O
version	O
of	O
"	O
Project	O
Composer	O
"	O
,	O
a	O
previous	O
iteration	O
of	O
the	O
service	O
with	O
roots	O
from	O
the	O
acquisition	O
of	O
Hackpad	B-Application
in	O
April	O
2014	O
.	O
</s>
<s>
In	O
October	O
2015	O
,	O
Dropbox	B-Application
announced	O
the	O
upcoming	O
launch	O
of	O
Dropbox	B-Application
Paper	I-Application
,	O
its	O
collaborative	O
document	O
editor	O
,	O
noted	O
by	O
the	O
media	O
as	O
the	O
result	O
of	O
its	O
development	O
of	O
a	O
Dropbox	B-Application
Notes	O
service	O
earlier	O
in	O
2015	O
.	O
</s>
<s>
Dropbox	B-Application
Paper	I-Application
entered	O
open	O
beta	O
in	O
August	O
2016	O
,	O
allowing	O
anyone	O
to	O
join	O
and	O
test	O
the	O
product	O
.	O
</s>
<s>
Mobile	O
apps	O
for	O
Android	B-Application
and	O
iOS	B-Application
were	O
also	O
released	O
.	O
</s>
<s>
In	O
January	O
2017	O
,	O
Dropbox	B-Application
Paper	I-Application
was	O
officially	O
launched	O
.	O
</s>
<s>
Aimed	O
for	O
businesses	O
,	O
Dropbox	B-Application
Paper	I-Application
was	O
described	O
as	O
"	O
one	O
part	O
online	O
document	O
,	O
one	O
part	O
collaboration	O
,	O
one	O
part	O
task	O
management	O
tool	O
,	O
one	O
part	O
content	O
hub	O
"	O
by	O
Rob	O
Baesman	O
,	O
Dropbox	B-Application
's	O
head	O
of	O
product	O
,	O
and	O
allows	O
for	O
importing	O
,	O
editing	O
,	O
and	O
collaboration	O
on	O
"	O
a	O
number	O
of	O
other	O
file	O
types	O
from	O
Google	O
,	O
Microsoft	O
,	O
and	O
others	O
"	O
.	O
</s>
<s>
Users	O
have	O
devised	O
a	O
number	O
of	O
uses	O
for	O
and	O
mashups	B-Application
of	O
the	O
technology	O
that	O
expand	O
Dropbox	B-Application
's	O
functionality	O
.	O
</s>
<s>
These	O
include	O
:	O
sending	O
files	O
to	O
a	O
Dropbox	B-Application
via	O
Gmail	B-Application
;	O
using	O
Dropbox	B-Application
to	O
sync	O
instant	B-Application
messaging	I-Application
chat	O
logs	O
;	O
BitTorrent	B-Protocol
management	O
;	O
password	O
management	O
;	O
remote	B-Protocol
application	I-Protocol
launching	I-Protocol
and	O
system	O
monitoring	O
;	O
and	O
as	O
a	O
free	O
web	O
hosting	O
service	O
.	O
</s>
<s>
Dropbox	B-Application
has	O
received	O
several	O
awards	O
,	O
including	O
the	O
Crunchie	O
Award	O
in	O
2010	O
for	O
Best	O
Internet	O
Application	O
,	O
and	O
Macworlds	O
2009	O
Editor	O
's	O
Choice	O
Award	O
for	O
Software	O
.	O
</s>
<s>
Dropbox	B-Application
's	O
mobile	O
iPhone	B-Device
app	O
release	O
in	O
2010	O
was	O
among	O
the	O
top	O
10	O
"	O
best	O
apps	O
"	O
selected	O
by	O
Alex	O
Ahlund	O
,	O
former	O
CEO	O
of	O
two	O
websites	O
focused	O
on	O
mobile	O
apps	O
,	O
and	O
the	O
company	O
's	O
Android	B-Application
app	O
was	O
also	O
selected	O
as	O
one	O
of	O
the	O
top	O
five	O
"	O
best	O
apps	O
"	O
in	O
a	O
list	O
compiled	O
in	O
2010	O
by	O
Jason	O
Hiner	O
for	O
ZDNet	O
.	O
</s>
<s>
In	O
2011	O
,	O
Business	O
Insider	O
named	O
Dropbox	B-Application
the	O
world	O
's	O
sixth	O
most	O
valuable	O
startup	O
,	O
and	O
in	O
2017	O
,	O
the	O
publication	O
ranked	O
Dropbox	B-Application
as	O
the	O
eighth	O
most	O
valuable	O
US	O
startup	O
,	O
with	O
a	O
valuation	O
of	O
$10	O
billion	O
.	O
</s>
<s>
Apple	O
launched	O
its	O
own	O
cloud	B-Application
storage	I-Application
service	I-Application
later	O
in	O
2011	O
,	O
iCloud	B-Application
,	O
but	O
this	O
did	O
n't	O
hold	O
back	O
Dropbox	B-Application
's	O
growth	O
.	O
</s>
<s>
In	O
January	O
2012	O
,	O
Dropbox	B-Application
was	O
named	O
startup	O
of	O
the	O
year	O
by	O
TechCrunch	O
,	O
and	O
in	O
2016	O
,	O
the	O
company	O
was	O
ranked	O
#2	O
on	O
the	O
Forbes	O
Cloud	O
100	O
list	O
.	O
</s>
<s>
Dropbox	B-Application
has	O
been	O
the	O
subject	O
of	O
criticism	O
and	O
controversy	O
related	O
to	O
multiple	O
incidents	O
,	O
including	O
a	O
June	O
2011	O
authentication	O
problem	O
that	O
let	O
accounts	O
be	O
accessed	O
for	O
several	O
hours	O
without	O
passwords	O
;	O
a	O
July	O
2011	O
Privacy	O
Policy	O
update	O
with	O
language	O
suggesting	O
Dropbox	B-Application
had	O
ownership	O
of	O
users	O
 '	O
data	O
;	O
concerns	O
about	O
Dropbox	B-Application
employee	O
access	O
to	O
users	O
 '	O
information	O
;	O
July	O
2012	O
email	O
spam	O
with	O
recurrence	O
in	O
February	O
2013	O
;	O
leaked	O
government	O
documents	O
in	O
June	O
2013	O
with	O
information	O
that	O
Dropbox	B-Application
was	O
being	O
considered	O
for	O
inclusion	O
in	O
the	O
National	O
Security	O
Agency	O
's	O
PRISM	O
surveillance	O
program	O
;	O
a	O
July	O
2014	O
comment	O
from	O
NSA	O
whistleblower	O
Edward	O
Snowden	O
criticizing	O
Dropbox	B-Application
's	O
encryption	O
keys	O
being	O
available	O
to	O
employees	O
;	O
the	O
leak	O
of	O
68million	O
account	O
passwords	O
on	O
the	O
Internet	O
in	O
August	O
2016	O
;	O
and	O
a	O
January	O
2017	O
accidental	O
data	O
restoration	O
incident	O
where	O
years-old	O
supposedly	O
deleted	O
files	O
reappeared	O
in	O
users	O
 '	O
accounts	O
.	O
</s>
<s>
While	O
Dropbox	B-Application
uses	O
SSL	B-Protocol
to	O
encrypt	O
data	O
in	O
transit	O
between	O
itself	O
and	O
customers	O
,	O
it	O
stores	O
data	O
in	O
encrypted	O
form	O
and	O
does	O
not	O
use	O
end-to-end	O
encryption	O
in	O
which	O
the	O
user	O
controls	O
the	O
keys	O
used	O
to	O
encrypt	O
the	O
stored	O
data	O
.	O
</s>
<s>
As	O
a	O
result	O
,	O
Dropbox	B-Application
can	O
decrypt	O
customers	O
 '	O
data	O
if	O
it	O
chooses	O
to	O
.	O
</s>
<s>
The	O
Dropbox	B-Application
headquarters	O
,	O
located	O
in	O
San	O
Francisco	O
,	O
were	O
originally	O
on	O
Market	O
Street	O
,	O
until	O
its	O
expansion	O
to	O
the	O
China	O
Basin	O
Landing	O
building	O
in	O
July	O
2011	O
,	O
allowing	O
for	O
a	O
significant	O
space	O
increase	O
.	O
</s>
<s>
In	O
December	O
2012	O
,	O
Dropbox	B-Application
set	O
up	O
an	O
office	O
in	O
Dublin	O
,	O
Ireland	O
,	O
its	O
first	O
office	O
outside	O
the	O
United	O
States	O
.	O
</s>
<s>
Dropbox	B-Application
expanded	O
into	O
its	O
second	O
U.S.	O
office	O
in	O
Austin	O
,	O
Texas	O
in	O
February	O
2014	O
.	O
</s>
<s>
The	O
State	O
of	O
Texas	O
and	O
City	O
of	O
Austin	O
provided	O
a	O
$1.7	O
million	O
performance-based	O
incentives	O
package	O
to	O
Dropbox	B-Application
in	O
exchange	O
for	O
locating	O
their	O
office	O
in	O
Austin	O
.	O
</s>
<s>
In	O
April	O
,	O
of	O
the	O
same	O
year	O
,	O
Dropbox	B-Application
opened	O
an	O
office	O
in	O
Sydney	O
,	O
Australia	O
.	O
</s>
