SLOWR
Men’s wellness, reimagined as a product.
A complete iOS experience built around guided training, progressive programs, education, progress tracking and subscriptions.
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Designed. Built. Shipped by Cortexity.
Your app idea. Built in 21 days.
You bring the idea. We take care of everything else.
Strategy. Design. Development. Testing. App Store submission.
One project. One fixed price. $5,000.
One new project a month.
Apps shipped by Cortexity: SLOWR, ReflexFlow.
You’ve had the idea. Now make it real.
Most app ideas never make it out of the Notes app.
Maybe it’s been sitting in your Notes for six months.
Maybe you’ve talked about it with friends.
Maybe you can already picture exactly how it should work. You just have no idea how to actually build it.
And when you start looking into development, you’re completely overwhelmed:
Designers. Developers. Technical decisions. Quotes. Timelines. APIs. Databases. Architecture. Bugs. Unresponsive developer. Vague answers. No updates for two weeks. App Store rejections.
Suddenly, building your idea feels like too much stress.
It can be simple AND easy.
That’s our job.
Bring us the idea.
We’ll help you think through the product, design it, build it, refine it with you, and turn it into a real iPhone app.
21 days. $5,000. Done for you.
Tell Us Your IdeaI personally review every application.
An idea today. A real product 21 days later.
From one sentence to a working iPhone app.
Day 1
“What if there was an app that showed me every available padel court nearby and let me book one instantly?”
That’s enough to start.
Your idea doesn’t need to arrive as a specification.
You don’t need wireframes.
You don’t need technical knowledge.
You don’t need to know what database to use, which API you need, or how the app should be architected.
You just need the idea.
We take it from there.
21 days later
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A beautifully designed, working iPhone app.
Something you can hold in your hand.
Something you can show people.
Something your first customers can actually use.
That’s the transformation you’re paying for.
Apply to Build Your AppI personally review every application.
The Founder
One person responsible for getting it done.
You work directly with me, from the first call to the App Store.
Hi, I’m Joseph, founder of Cortexity. I design and build iPhone apps for founders, from the first call to the App Store.
Before building apps for other founders, I built my own. I’ve been the client. The delays, the vague answers, the “that wasn’t in the scope”. That’s why Cortexity exists.
When I take on your app, I take responsibility for getting it built. You shouldn’t have to project-manage your developer or understand the technology. You should feel free to change your mind when the product could be better.
For 21 days we work on one goal: the best first version of your app we can build. You bring the vision. I’ll take care of the rest.
And yes, I’m the one who answers your messages.
What’s Included
Everything between the idea and the App Store.
Product, design, development and launch, handled by one person.
Cortexity handles the whole process.
Product
We turn what’s in your head into a first version worth building.
Design
Every screen and every interaction, designed so you’re proud to put your name on it.
Development
App, backend, database, APIs. You never need to know what any of it means.
Refinement
You see it as it’s built. Change your mind as often as you like. No hourly bill.
Launch
We submit it to the App Store and stay with you through review.
Built by Cortexity.
A few of the apps we’ve built, live on the App Store today.
ReflexFlow
A private guided wellness experience for women.
A multi-week iOS program combining guided audio, progressive training and personal progress tracking.
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Designed. Built. Shipped by Cortexity.
The Process
What the next 21 days look like.
Three weeks, three phases, one working app.
- 1
Week 1
We understand the idea.
One conversation. Then we design.
- We talk through the idea, who it’s for, and how you imagine it working.
- We define the main features for version one.
- First screens on your phone by the end of the week.
- 2
Week 2
We make it real.
Screens become flows. Flows become features.
- The core of the app works, on your iPhone.
- You use it every day and tell me what feels wrong.
- We change it. Nothing extra to pay.
- 3
Week 3
We make it better. Then we ship.
The details that make it feel finished.
- Refinement and polish, together.
- App Store submission, handled with you.
- The app, the design, the code: yours.
No Scope Creep
No “that’s outside the scope” every time you have an idea.
Changing your mind is part of building something good.
A product you imagined three weeks ago won’t always be the product you want after you’ve actually seen and used it.
That’s normal.
For the 21 days we’re working together, you’re not going to be charged every time you ask us to change a button, rethink a screen or improve how something works.
Ask for changes as often as you like.
There is no hourly bill.
There is no awkward conversation because you’ve used your allotted number of revisions.
We’re building the product together.
If you ask for a big change that needs more time, we’ll adjust the timeline together.
But our default response to a better idea isn’t:
“That’s outside the scope.”
It’s:
“Let’s figure out how to make it work.”
Who It’s For
This is for founders who are serious about building.
For founders ready to stop thinking about it and build it.
Cortexity is for you if you’ve been thinking about an app for too long, or if you’ve tried to build one before and it went badly.
You don’t need to be technical.
You don’t need to have founded a company before.
You don’t even need to have every detail figured out.
But you do need to show up.
We want founders who answer messages, give feedback, make decisions and genuinely want to see their product exist.
In return, you’ll get that same commitment from me.
We deliberately take on very few projects because when we’re building yours, we want to be all in.
If you’re casually exploring an idea, looking for the cheapest possible developer, or collecting ten quotes before deciding whether you even want to build anything, we’re probably not the right fit.
If you’re thinking:
“I want to finally build this properly.”
Then we should talk.
Tell Us What You Want to BuildI personally review every application.
Pricing
$5,000. Start to finish.
One fixed price, paid in two halves.
No hourly rate.
No paying a designer separately.
No development bill that grows every week.
No paying extra because you asked for another revision during the project.
Your Cortexity build: $5,000
$2,500 to start.
$2,500 when your app is finished.
That includes the 21-day product build, design, development, testing, refinement, App Store submission and full ownership of the finished project.
iPhone
$5,000
- Product strategy
- Full app design
- Development
- Backend, database & APIs
- Testing
- Refinement throughout the build
- App Store submission
- Full ownership of the app and code
Apply to Build Your AppNo payment until we’ve spoken and both said yes.
iPhone + Android
$8,000
- Product strategy
- Full app design
- Development
- Backend, database & APIs
- Testing
- Refinement throughout the build
- App Store submission
- Full ownership of the app and code
- Android built as a second phase
Apply to Build Your AppNo payment until we’ve spoken and both said yes.
Before you pay anything, I’ll talk with you about your idea.
I’ll make sure I understand what you want to build and that Cortexity is the right studio for it. If it isn’t, I’ll tell you.
FAQ
Questions you probably have.
Straight answers to what founders ask first.
Can you really build my app in 21 days?
Yes. That’s the promise.
Before we start, we talk through the idea so I know exactly what we’re building.
What if I change my mind about something halfway through?
That’s expected. Changing your mind is part of the process.
Seeing the real app always changes how you think about it. That’s normal.
During the 21 days, we’ll keep refining the product with you. You’re not going to receive an extra invoice because you wanted a screen redesigned or realized something should work differently.
If you make a major change that affects the 21-day timeline, I’ll tell you right away and we’ll adjust the delivery date together.
What happens after the 21 days?
Once the build is complete, the app is yours.
We’ll then handle the App Store submission process with you.
Want to keep building after that? New features and bigger updates are a new project, priced on its own.
You’re not locked into Cortexity.
What if something breaks after the project?
If something we delivered isn’t working the way it’s supposed to, we’ll fix it.
We’re not going to hand you the app on Day 21 and pretend we’ve never met.
For new features, redesigns or continued product development after the initial project, we simply start a new project together, billed separately.
Can you build Android too?
Yes. iPhone is $5,000. iPhone plus Android is $8,000.
We build the iPhone app first, then the Android version, so each one feels native.
Tell us in your application if you want both.
Is App Store submission included?
Yes.
We handle the submission process after the 21-day build.
Apple controls the review and approval process, so the time Apple takes to approve an app isn’t counted as part of the 21 days.
If Apple comes back with something that needs addressing, we’ll work through it until the app is live.
Do I own everything?
Yes.
Once the project is completed and the final payment is made, the finished app, code and project are yours.
It’s your product.
How is payment made?
Payment is made via Whish.
The project starts once the 50% deposit is received.
Do I need to know anything about building apps?
No.
You shouldn’t have to.
You know the idea, the customer and the problem you’re trying to solve.
We take care of the rest.
Three weeks from now, this could be on your iPhone.
Tell me about the idea. I read every application myself.
Stop telling people about it.
Hand them the app instead.
If you have an app idea you’re serious about, tell us about it.
I’ll personally review what you send.
If I think Cortexity is the right fit, I’ll contact you directly and we’ll talk about the product.
Your idea. Our responsibility.
21 days. $5,000.
Apply to Build Your AppI personally review every application.
One new project a month.