I Built a $20K/Month App in 83 Days
Starter Story
May 11, 2026
In this video, we break down how a simple mobile app turned into a $20K/month business. But the real story is about how he validated the idea BEFORE writing a single line of code. By the end of this video, you will have playbook you can use to go validate your app.
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Chapters:
0:00 - The commitment metric
0:56 - Meet Brian Shin
1:27 - Business breakdown
2:35 - Mobile app growth tactics
3:22 - Founder background
4:25 - App idea
5:48 - Build process
6:35 - Tech Stack
7:07 - Validating the app
8:30 - Validation Playbook
11:23 - How the app works
12:18 - Stop overthinking!
13:15 - Pat and Gus reflections
Chapters
Stack
Transcript
Chapters
Stack
No tools listed for this business.
This
started
as
a
fun
side
project
but
we
turned
it
into
a
real
business
Meet
Brian
him
and
his
girlfriend
built
a
really
simple
mobile
app
And
in
less
than
three
months
they
grew
it
to
over
20
000
a
month
We
set
a
number
and
didn't
start
building
until
we
hit
it
You
might
think
he
validated
the
idea
like
everyone
else
but
no
he
did
something
I've
never
seen
before
And
it's
called
the
commitment
metric
We
made
sure
that
people
committed
to
this
product
before
writing
a
single
line
of
code
So
I
brought
Brian
onto
the
channel
to
break
it
all
down
for
me
And
in
this
episode
we'll
dive
into
the
amazingly
simple
app
that
makes
over
20
000
a
month
why
you
should
resist
the
temptation
to
build
anything
until
you
hit
this
one
number
and
the
new
framework
to
validate
business
ideas
in
an
AI
world
This
one
is
a
great
story
So
let's
dive
in
I'm
Pat
Walls
and
this
is
Starter
Story
All
right
Welcome
Brian
to
the
channel
Tell
me
about
who
you
are
what
app
you
built
and
what's
your
story
Hey
Pat
nice
to
meet
you
My
name
is
Brian
Shin
and
we
built
a
disposable
camera
app
called
ONCE
We
launched
back
in
December
2025
And
fortunately
we
were
able
to
hit
20K
in
monthly
revenue
within
83
days
of
launch
So
today
I
really
want
to
share
exactly
how
we
pre
validated
ONCE
before
writing
a
single
line
of
code
and
also
some
of
the
growth
playbooks
that
we
had
to
grow
ONCE
from
zero
all
the
way
to
20
000
in
monthly
revenue
Okay
cool
I
mean
awesome
to
have
you
here
Would
you
be
able
to
just
explain
what
your
app
does
who
uses
it
and
pull
up
some
of
your
revenue
dashboards
to
show
that
this
is
legit
to
the
audience
Yeah
for
sure
So
ONCE
is
basically
a
disposable
camera
for
events
especially
weddings
birthday
parties
and
these
days
even
for
some
corporate
events
So
anything
where
a
group
of
people
can
come
together
have
fun
and
capture
all
the
candid
moments
ONCE
can
play
a
role
there
And
our
pricing
is
based
on
the
number
of
guests
that
you
want
to
invite
into
your
event
So
if
it's
like
a
small
party
with
just
10
people
it's
going
to
be
just
2
But
if
it's
like
a
bigger
wedding
for
instance
if
it's
like
150
people
it'll
be
50
So
that's
the
more
usage
the
more
guests
the
more
higher
tier
that
you
would
need
to
purchase
in
order
to
use
ONCE
So
it's
been
around
three
months
since
launching
and
our
weekly
active
users
is
around
10
000
to
12
000
users
at
the
moment
And
in
terms
of
revenue
this
month
we're
totaling
around
22
000
And
this
is
our
internal
dashboard
calendar
where
you
can
see
all
of
our
active
users
who
have
scheduled
an
event
through
ONCE
And
as
you
can
see
in
February
there
are
around
more
than
300
events
And
for
March
we
got
around
700
events
coming
up
real
soon
Here's
what
I
love
about
Brian's
story
It's
a
great
example
of
someone
who
focused
on
growth
and
then
hit
20
000
a
month
in
less
than
90
days
And
this
got
me
thinking
we
talked
to
dozens
of
mobile
app
founders
every
week
right
here
on
this
channel
And
I
always
ask
them
the
same
question
How
did
you
actually
grow
your
app
Well
since
we
talked
to
so
many
people
we
decided
to
turn
all
of
their
answers
into
a
free
guide
that
you
can
download
right
now
It's
called
the
Mobile
App
Growth
Cheat
Sheet
And
inside
you
will
find
the
seven
different
marketing
tactics
that
are
working
for
real
founders
right
now
making
money
with
mobile
apps
If
you're
ready
to
focus
on
growth
and
actually
grow
your
app
just
head
to
the
first
link
in
the
description
to
download
the
entire
guide
for
free
I
promise
it
won't
disappoint
All
right
let's
get
back
to
the
episode
Okay
cool
I
mean
this
looks
like
a
really
cool
app
I
can
see
why
it's
popular
and
why
it's
growing
I
want
to
understand
a
little
bit
about
your
background
How
do
you
get
to
this
point
where
you're
building
this
cool
consumer
app
that
over
300
people
are
about
to
use
this
month
at
events
What's
your
background
So
before
founding
ONCE
I
co
founded
a
venture
backed
B2B
startup
It's
completely
different
from
ONCE
It
was
more
of
a
heavy
sales
driven
50
person
company
So
building
this
venture
backed
startup
really
showed
me
what
a
real
business
is
and
everything
related
to
building
a
fast
growth
company
And
while
I
was
at
the
company
I
found
the
whole
bootstrap
scene
which
I
didn't
know
existed
before
I
met
all
of
these
really
cool
indie
hackers
and
bootstrap
founders
who
are
validating
in
a
very
small
way
but
it's
rather
a
safer
smaller
bet
as
opposed
to
betting
your
whole
life
on
something
that's
bigger
And
I
don't
think
there's
right
or
wrong
here
but
I
really
wanted
to
try
this
new
path
of
building
a
bootstrap
company
And
that's
why
this
time
I
really
wanted
full
control
over
the
product
that
we
build
Hence
me
and
my
co
founder
my
girlfriend
we
decided
to
go
fully
bootstrap
this
time
Okay
cool
Let's
switch
topics
a
little
bit
and
talk
about
the
idea
So
how
do
you
actually
find
the
idea
for
this
app
that
eventually
makes
over
20
000
a
month
The
whole
story
comes
from
me
and
my
co
founder
who's
my
girlfriend
Just
last
year
we
traveled
to
almost
seven
eight
different
countries
and
every
single
city
we
go
to
we
bring
around
a
disposable
camera
If
you
tried
using
a
disposable
camera
it's
such
a
simple
product
but
it's
so
magical
in
a
way
that
it
has
so
many
limitations
You
can't
see
the
photo
right
away
You
have
limited
amount
of
shots
But
I
think
those
limitations
it
actually
makes
the
whole
experience
much
real
So
really
the
whole
idea
behind
ONCE
was
why
don't
we
try
to
build
a
digital
experience
that
almost
replicates
that
traditional
disposable
camera
was
the
whole
idea
behind
it
That's
awesome
Let's
talk
about
how
you
built
this
How
long
did
it
take
to
build
this
app
and
what
was
that
journey
like
So
the
first
version
took
around
a
week
or
two
It
was
a
web
app
that
kind
of
just
had
the
core
features
of
what
a
mobile
app
intended
to
have
We
had
a
Halloween
party
hosted
by
my
friend
coming
up
So
we
built
out
this
web
version
We
printed
out
some
invitation
codes
so
that
everyone
in
the
party
can
join
in
take
photos
And
honestly
it
broke
many
times
during
the
event
But
we
were
able
to
validate
the
core
idea
that
people
love
taking
photos
in
event
into
a
singular
album
of
each
other
through
an
experience
that
mocks
the
whole
disposable
camera
experience
So
it
didn't
need
to
be
perfect
but
it
was
perfect
enough
to
validate
what
we
wanted
to
check
My
other
question
is
AI
I
mean
you
just
built
this
like
three
months
ago
Did
you
just
build
it
with
AI
tools
or
what
tools
did
you
use
It
might
be
a
hot
take
but
after
we
validated
with
the
web
app
we
threw
out
the
first
version
And
that's
because
I
honestly
believe
that
consumer
app
is
basically
a
craft
And
I
use
a
lot
of
AI
for
dev
for
finance
for
everything
But
for
design
we
never
use
AI
And
that's
because
we
really
believe
that
design
requires
taste
And
we
think
that
the
more
opinionated
the
better
design
that
could
possibly
come
out
But
aside
from
that
I
basically
live
on
cloud
code
Yeah
I
mean
I
100
percent
agree
with
that
Design
is
one
of
those
things
that
AI
is
not
that
good
at
yet
And
when
you
have
a
B2C
app
like
this
a
consumer
facing
app
you
want
it
to
feel
this
isn't
just
for
utility
This
is
for
fun
creativeness
So
I
agree
on
that
Let's
talk
about
the
tech
stack
What
did
you
actually
use
to
build
this
All
of
our
designs
live
inside
Figma
And
for
the
dev
part
I
feel
like
I'm
stuck
with
cloud
code
And
I
started
off
with
just
a
single
terminal
instance
of
cloud
code
max
But
I
was
recommended
this
tool
called
Conductor
where
you
can
run
several
instances
of
cloud
code
to
work
on
different
work
trees
at
the
same
time
And
we
use
Superbase
for
our
database
and
backend
The
web
app
used
to
live
on
Purcell
but
we
still
have
it
running
web
aspects
of
the
product
OK
cool
We
talk
a
lot
about
building
but
I
think
maybe
the
more
important
thing
here
is
validating
So
tell
me
about
how
you
validated
once
I
did
two
things
to
validate
our
product
and
to
get
their
first
customers
The
most
obvious
thing
that
you
can
do
is
just
go
through
your
personal
network
And
what
I
do
is
I
open
up
three
different
tabs
I
have
my
X
open
I
have
my
LinkedIn
open
and
I
have
my
Instagram
or
Facebook
open
up
I
have
my
friends
list
I
just
go
through
every
single
one
of
them
and
see
who
might
be
a
good
fit
So
literally
I
circled
everyone
who
had
a
potential
event
coming
up
And
it
was
four
friends
who
said
OK
I
would
love
to
try
it
It
was
a
Halloween
party
birthday
party
one
wedding
and
one
networking
event
So
this
is
the
second
part
Now
you
have
to
go
outside
of
your
inner
circle
and
really
try
to
reach
out
to
everyone
who
could
be
your
potential
customers
So
what
I
did
was
since
ones
could
be
used
at
parties
at
events
at
weddings
I
searched
on
Instagram
hashtag
wedding
hashtag
birthday
party
and
cross
platform
We
had
around
250
to
300
people
listed
out
I
wrote
down
a
very
simple
cold
message
type
of
two
to
three
sentences
max
that
could
grab
their
attention
and
try
to
pitch
our
idea
so
that
they
can
try
it
out
Amongst
the
250
people
we
got
around
15
people
who
reached
back
and
we
got
around
12
events
fixed
for
that
single
month
And
that's
when
me
and
my
co
founder
decided
OK
this
does
have
market
potential
Let's
try
to
go
all
in
and
try
to
build
out
something
that's
really
cool
This
is
awesome
I've
never
heard
of
validation
in
this
sort
of
framing
before
So
let's
talk
about
this
a
little
bit
more
You
got
your
app
from
zero
to
20K
in
basically
83
days
If
you
had
to
start
over
today
what
would
be
your
playbook
Step
one
would
be
to
define
your
commitment
metric
And
commitment
here
means
two
different
things
Commitment
for
yourself
and
commitment
for
your
potential
users
as
well
For
yourself
set
a
specific
date
and
specific
number
of
customers
or
clients
or
other
metrics
that
you
would
like
to
see
within
that
date
range
And
at
least
you
know
that
this
is
a
finite
number
of
days
that
you
are
dedicating
and
investing
to
validate
your
business
in
a
certain
amount
of
time
And
the
commitment
metric
of
the
client
to
signal
validation
doesn't
always
need
to
be
payment
So
for
us
it
was
event
hosts
using
our
product
within
those
events
So
based
on
your
vertical
based
on
your
product
there
must
be
some
type
of
metric
that
truly
represents
usage
And
yeah
once
you
have
that
commitment
metric
out
I
guess
step
two
would
be
to
exhaust
your
personal
network
Just
open
up
all
of
your
social
media
profiles
and
try
to
see
who
you
can
reach
out
to
whoever
relevant
to
your
ideal
customer
profile
And
one
of
the
most
important
things
when
talking
to
your
friends
and
family
is
a
very
famous
concept
but
it's
called
the
mom
test
which
is
you
try
to
validate
a
product
with
your
mother
She
would
probably
be
very
excited
about
whatever
you
build
And
that
is
honestly
not
the
best
way
to
validate
your
product
So
just
be
honest
with
yourself
so
that
you
are
sure
that
you're
validating
the
product
as
opposed
to
trying
to
find
encouragement
for
your
product
So
that's
step
two
Well
step
three
is
the
real
part
which
is
to
build
a
quick
mockup
Don't
spend
more
than
two
to
three
days
with
this
Just
go
on
Figma
or
just
use
many
of
these
AI
tools
that's
out
there
No
matter
how
scrappy
it
is
just
try
to
find
that
really
simple
product
that
you
can
present
to
your
users
your
users
And
once
you
have
that
step
four
is
to
go
wherever
your
users
are
living
in
and
are
active
in
Just
start
from
zero
Go
to
Reddit
learn
the
ins
and
outs
of
Reddit
if
Reddit
is
the
place
to
be
or
if
that's
TikTok
or
if
that's
YouTube
because
this
channel
will
not
only
be
used
for
validation
but
if
the
validation
works
it'll
be
your
main
marketing
channel
in
the
future
also
So
do
so
much
cold
mailing
cold
messaging
Honestly
what
I
tell
other
friends
and
founders
is
that
if
you
haven't
been
banned
in
these
platforms
at
least
two
times
you
haven't
tried
enough
And
step
five
is
to
set
that
number
that
gives
you
enough
signal
or
confidence
that
this
product
has
potential
For
us
internally
the
goal
was
simple
Before
writing
a
single
line
of
code
I
needed
ten
events
with
an
actual
date
with
an
actual
commitment
that
they
would
like
to
try
using
out
the
product
Having
a
commitment
to
actually
use
at
an
event
where
you
have
your
friends
your
family
your
loved
ones
there
We
thought
that
was
already
a
big
enough
commitment
that
it
was
almost
proxy
to
a
payment
So
this
would
be
the
exact
playbook
that
I
would
be
using
if
I
had
to
start
all
over
today
Well
I
love
this
validation
playbook
I
think
a
lot
of
people
watching
this
go
rewind
start
it
over
watch
it
again
This
sort
of
commitment
metric
this
restraint
thing
sounds
scary
It
sounds
hard
but
it
will
save
you
so
much
time
not
building
the
wrong
thing
So
I
love
that
Let's
switch
topics
a
little
bit
I
want
to
see
your
app
Can
you
give
me
a
demo
of
your
app
that
made
over
20
000
last
month
Our
app
is
really
simple
And
what
you
can
do
is
create
your
own
film
You
name
your
own
film
let's
say
Brian's
Party
And
you
can
choose
the
date
it
ends
choose
when
your
photos
reveal
like
a
disposable
camera
your
filters
some
of
the
invitation
card
when
you
invite
your
guests
And
you
can
also
choose
how
many
participants
you
want
to
invite
and
the
shots
per
person
you
wait
out
until
your
film
is
created
Once
it
is
you
can
start
taking
photos
And
yeah
like
a
disposable
camera
this
will
all
be
saved
up
And
based
on
your
reveal
settings
this
might
reveal
later
or
might
reveal
now
And
you
can
check
everyone's
photos
in
this
album
where
everyone's
photos
photos
all
gather
up
in
one
area
Cool
OK
well
that's
an
awesome
app
I
love
apps
like
this
Super
cool
Last
question
that
we
ask
all
founders
to
come
on
Starter
Story
What
would
be
your
advice
to
young
Brian
or
for
anyone
watching
this
who
wants
to
come
up
with
a
cool
app
idea
like
you
make
money
do
indie
hacking
What
would
be
your
advice
I
think
the
most
important
would
be
to
stop
overthinking
and
just
launch
because
I
used
to
be
a
person
who
overthinks
a
lot
How
do
I
do
marketing
How
do
I
do
sales
La
la
la
la
la
But
I
realize
that
those
are
really
not
the
most
important
things
If
you're
trying
to
go
zero
to
one
rather
just
spend
that
time
talking
to
more
users
and
just
building
out
the
very
first
version
in
like
a
week
or
two
maximum
and
just
launch
because
all
of
your
assumptions
and
all
of
your
guesswork
may
go
to
nothing
once
you
launch
And
once
users
start
using
it
you
might
be
solving
a
whole
new
different
problem
than
what
you
were
initially
expecting
So
really
stop
overthinking
and
launch
as
fast
as
possible
Thanks
for
coming
on
Brian
and
sharing
super
cool
app
I
think
it's
going
to
grow
a
lot
Thanks
for
coming
on
and
sharing
everything
All
right
man
Thanks
a
lot
All
right
Gus
from
Starter
Story
What
do
you
think
of
this
business
This
app
wants
film
First
thought
is
really
cool
product
A
lot
of
mobile
app
founders
we
talk
to
I
feel
like
we've
seen
it
before
to
some
degree
I
haven't
exactly
seen
an
app
quite
like
this
I
know
that
probably
does
exist
But
that's
my
first
thought
is
like
just
a
cool
product
and
a
cool
dude
A
lot
of
people
have
weddings
and
want
this
sort
of
thing
in
this
social
media
organic
world
that
we
live
in
I
had
a
wedding
You
had
a
wedding
I'm
sure
you
get
all
these
like
professional
photographs
but
they're
like
super
lame
and
you
don't
even
post
those
to
social
media
You
just
post
like
the
selfies
you
took
or
or
whatever
So
I
actually
think
this
is
like
from
a
growth
perspective
This
app
is
going
to
be
huge
Maybe
we
can
have
him
back
on
the
channel
when
I
think
it's
going
to
grow
fast
and
hits
you
know
a
million
dollars
a
year
or
wherever
it
gets
And
we
can
talk
more
about
the
growth
of
that
So
let
us
know
in
the
comments
if
you
want
to
see
us
talk
more
about
how
he
grew
that
I
think
his
validation
strategy
was
really
smart
What
do
you
think
about
that
Yeah
that
is
really
like
compelling
because
you
know
I've
tried
to
start
like
my
apps
and
stuff
like
that
and
I
totally
fall
into
the
trap
of
like
building
it
first
And
with
Codco
and
all
these
AI
tools
it
makes
it
so
easy
to
do
it
and
then
avoid
the
hard
part
You
know
when
he
when
he
was
talking
about
like
go
through
your
contacts
and
reach
out
to
people
man
I
could
feel
myself
sort
of
like
cringing
up
a
little
like
I
can't
imagine
like
messaging
messaging
a
random
person
from
10
years
ago
when
I
went
to
college
and
being
like
hey
I
built
this
like
what
do
you
think
But
I
think
that's
definitely
like
a
beginner's
mindset
You're
spot
on
with
that
Before
when
it
was
hard
to
build
stuff
you
had
to
ask
people
and
then
decide
you
would
build
it
That
would
be
like
the
natural
way
to
do
things
because
you
just
couldn't
build
it
Now
I
think
that
AI
tools
are
such
a
crutch
in
that
sense
Is
that
like
oh
I
have
a
cool
idea
Instead
of
talking
to
people
I'm
just
going
to
build
it
Then
you
build
it
It
works
and
it's
awesome
And
then
you
don't
know
what
to
do
next
You're
scared
It
doesn't
exactly
look
as
good
as
you
wanted
it
to
So
then
you
know
maybe
demotivates
you
from
doing
this
very
very
important
thing
which
is
sharing
it
with
random
people
that
you
haven't
talked
to
in
10
years
This
is
the
scary
stuff
So
I
hope
a
lot
of
people
watching
this
realize
that
oh
in
a
world
where
anyone
can
build
anything
in
one
hour
this
is
the
secret
sauce
going
out
and
setting
your
commitment
metric
of
I
need
10
people
to
say
they're
going
to
use
this
thing
before
I
finish
it
So
if
you're
thinking
about
doing
the
same
you
may
even
built
some
stuff
before
or
you're
thinking
about
jumping
into
cloud
code
and
starting
to
build
an
app
Stop
right
there
And
instead
go
click
the
link
in
the
description
to
learn
about
how
to
actually
grow
and
validate
a
mobile
app
We
put
together
the
top
growth
strategies
for
growing
a
mobile
app
an
iOS
app
a
B2C
app
You
can
click
that
right
down
there
in
the
description
description
and
get
it
100
percent
for
free
All
right
I
hope
you
guys
enjoyed
this
episode
of
Star
Story
I'll
see
you
in
the
next
one
Peace
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