<s>
Mobile	B-Application
backend	I-Application
as	I-Application
a	I-Application
service	I-Application
(	O
MBaaS	B-Application
)	O
,	O
also	O
known	O
as	O
"	O
backend	B-Application
as	I-Application
a	I-Application
service	I-Application
"	O
,	O
is	O
a	O
model	O
for	O
providing	O
web	B-Application
app	I-Application
and	O
mobile	B-Application
app	I-Application
developers	O
with	O
a	O
way	O
to	O
link	O
their	O
applications	O
to	O
backend	B-Architecture
cloud	O
storage	O
and	O
APIs	B-Application
exposed	O
by	O
back	B-Architecture
end	I-Architecture
applications	O
while	O
also	O
providing	O
features	O
such	O
as	O
user	O
management	O
,	O
push	B-General_Concept
notifications	I-General_Concept
,	O
and	O
integration	O
with	O
social	O
networking	O
services	O
.	O
</s>
<s>
These	O
services	O
are	O
provided	O
via	O
the	O
use	O
of	O
custom	O
software	B-Application
development	I-Application
kits	I-Application
(	O
SDKs	B-Application
)	O
and	O
application	B-Application
programming	I-Application
interfaces	I-Application
(	O
APIs	B-Application
)	O
.	O
</s>
<s>
Web	O
and	O
mobile	B-Application
apps	I-Application
require	O
a	O
similar	O
set	O
of	O
features	O
on	O
the	O
backend	B-Architecture
,	O
including	O
notification	B-General_Concept
service	I-General_Concept
,	O
integration	O
with	O
social	O
networks	O
,	O
and	O
cloud	O
storage	O
.	O
</s>
<s>
Each	O
of	O
these	O
services	O
has	O
its	O
own	O
API	B-Application
that	O
must	O
be	O
individually	O
incorporated	O
into	O
an	O
app	O
,	O
a	O
process	O
that	O
can	O
be	O
time-consuming	O
and	O
complicated	O
for	O
app	O
developers	O
.	O
</s>
<s>
BaaS	O
providers	O
form	O
a	O
bridge	O
between	O
the	O
frontend	B-Architecture
of	O
an	O
application	O
and	O
various	O
cloud-based	O
backends	B-Architecture
via	O
a	O
unified	O
API	B-Application
and	O
SDK	B-Application
.	O
</s>
<s>
Providing	O
a	O
consistent	O
way	O
to	O
manage	O
backend	B-Architecture
data	O
means	O
that	O
developers	O
do	O
not	O
need	O
to	O
redevelop	O
their	O
own	O
backend	B-Architecture
for	O
each	O
of	O
the	O
services	O
that	O
their	O
apps	O
need	O
to	O
access	O
,	O
potentially	O
saving	O
both	O
time	O
and	O
money	O
.	O
</s>
<s>
Although	O
similar	O
to	O
other	O
cloud-computing	O
business	O
models	O
,	O
such	O
as	O
software	B-Architecture
as	I-Architecture
a	I-Architecture
service	I-Architecture
(	O
SaaS	B-Architecture
)	O
,	O
infrastructure	O
as	O
a	O
service	O
(	O
IaaS	O
)	O
,	O
and	O
platform	B-Application
as	I-Application
a	I-Application
service	I-Application
(	O
PaaS	B-Application
)	O
,	O
BaaS	O
is	O
distinct	O
from	O
these	O
other	O
services	O
in	O
that	O
it	O
specifically	O
addresses	O
the	O
cloud-computing	O
needs	O
of	O
web	O
and	O
mobile	B-Application
app	I-Application
developers	O
by	O
providing	O
a	O
unified	O
means	O
of	O
connecting	O
their	O
apps	O
to	O
cloud	O
services	O
.	O
</s>
<s>
Each	O
BaaS	O
provider	O
offers	O
a	O
slightly	O
different	O
set	O
of	O
backend	B-Architecture
tools	O
and	O
resources	O
.	O
</s>
<s>
Among	O
the	O
most	O
common	O
services	O
provided	O
are	O
notification	B-General_Concept
service	I-General_Concept
,	O
file	O
storage	O
and	O
sharing	O
,	O
integration	O
with	O
social	O
networks	O
such	O
as	O
Facebook	B-Application
and	O
Twitter	B-Application
,	O
location	B-Application
services	I-Application
,	O
database	O
persistence	O
and	O
queries	O
,	O
messaging	O
and	O
chat	O
functions	O
,	O
user	O
management	O
,	O
running	O
business	B-Architecture
logic	I-Architecture
,	O
and	O
usage	O
analysis	O
tools	O
.	O
</s>
<s>
BaaS	O
providers	O
have	O
a	O
broad	O
focus	O
,	O
providing	O
SDKs	B-Application
and	O
APIs	B-Application
that	O
work	O
for	O
app	O
development	O
on	O
multiple	O
platforms	O
,	O
such	O
as	O
iOS	B-Application
,	O
Android	B-Application
,	O
Blackberry	B-Application
,	O
Windows	B-Protocol
Phone	I-Protocol
,	O
HTML5	B-Application
,	O
and	O
others	O
.	O
</s>
<s>
Under	O
this	O
model	O
,	O
a	O
client	O
receives	O
a	O
certain	O
number	O
of	O
free	O
active	O
users	O
or	O
API	B-Application
calls	O
per	O
month	O
,	O
and	O
pays	O
a	O
fee	O
for	O
each	O
user	O
or	O
call	O
over	O
this	O
limit	O
.	O
</s>
<s>
Some	O
of	O
the	O
providers	O
offer	O
the	O
unlimited	O
API	B-Application
calls	O
inside	O
their	O
free	O
plan	O
offerings	O
.	O
</s>
<s>
While	O
BaaS	O
is	O
most	O
commonly	O
offered	O
as	O
a	O
commercial	O
service	O
,	O
open-source	B-Application
options	O
are	O
available	O
.	O
</s>
