<s>
Mailbox	B-Protocol
was	O
a	O
freeware	B-License
email	O
management	O
application	O
for	O
iOS	B-Application
and	O
Android	B-Application
,	O
developed	O
by	O
Orchestra	O
,	O
Inc	O
.	O
</s>
<s>
It	O
drew	O
the	O
attention	O
of	O
numerous	O
technology	O
blogs	O
for	O
its	O
usability	B-General_Concept
and	O
innovative	O
features	O
,	O
such	O
as	O
swipe-based	O
email	O
sorting	O
,	O
snoozing	O
and	O
filtering	O
.	O
</s>
<s>
Upon	O
its	O
iOS	B-Application
launch	O
on	O
7	O
February	O
2013	O
,	O
Mailbox	B-Protocol
became	O
the	O
second-most-downloaded	O
free	O
app	O
in	O
the	O
App	B-Application
Store	I-Application
that	O
day	O
.	O
</s>
<s>
In	O
March	O
2013	O
,	O
Orchestra	O
was	O
acquired	O
by	O
Dropbox	B-Application
.	O
</s>
<s>
The	O
rollout	O
of	O
Mailbox	B-Protocol
was	O
sped	O
up	O
and	O
the	O
pre-registration	O
period	O
ended	O
in	O
April	O
.	O
</s>
<s>
In	O
April	O
2014	O
,	O
Dropbox	B-Application
released	O
Mailbox	B-Protocol
for	O
Android	B-Application
and	O
announced	O
a	O
public	O
beta	O
version	O
for	O
,	O
which	O
was	O
released	O
in	O
August	O
.	O
</s>
<s>
In	O
December	O
2015	O
,	O
Dropbox	B-Application
announced	O
the	O
discontinuation	O
of	O
Mailbox	B-Protocol
,	O
saying	O
that	O
they	O
were	O
not	O
able	O
to	O
"	O
fundamentally	O
fix	O
email	O
"	O
with	O
it	O
and	O
that	O
they	O
rather	O
focus	O
on	O
"[streamlining]	O
the	O
workflows	O
that	O
generate	O
so	O
much	O
email	O
"	O
.	O
</s>
<s>
Mailbox	B-Protocol
focused	O
on	O
emptying	O
the	O
user	O
's	O
inbox	O
and	O
favored	O
using	O
folders	O
instead	O
of	O
leaving	O
emails	O
in	O
the	O
inbox	O
.	O
</s>
<s>
Mailbox	B-Protocol
was	O
limited	O
to	O
Gmail	B-Application
and	O
iCloud	B-Application
accounts	O
.	O
</s>
<s>
Setting	O
up	O
Mailbox	B-Protocol
required	O
granting	O
the	O
company	O
's	O
servers	O
access	O
to	O
the	O
user	O
's	O
email	O
account	O
,	O
either	O
through	O
APIs	B-Application
(	O
Gmail	B-Application
)	O
or	O
direct	O
access	O
(	O
iCloud	B-Application
)	O
.	O
</s>
<s>
Mailbox	B-Protocol
's	O
servers	O
repeatedly	O
queried	O
the	O
user	O
's	O
email	O
account	O
to	O
provide	O
push	B-General_Concept
notifications	I-General_Concept
and	O
allowed	O
the	O
application	O
to	O
refresh	O
its	O
content	O
without	O
having	O
to	O
run	O
in	O
the	O
background	O
for	O
prolonged	O
periods	O
.	O
</s>
