Most people start by asking what they should build. Fair enough, that's the fun question.
The duller one decides more: how does money actually get from someone's bank account into yours? There are about six answers, and once you pick one, a lot of things that felt like choices turn out to have been decided for you.
The six ways
A subscription means people pay every month or year and keep paying. Spotify, and most apps with a Pro button somewhere.
A one-time purchase means they pay once and own it. Paid games, or that £4 utility you bought two years ago and forgot about.
Freemium is free for everybody, with money coming from the small slice who want more. Most of the popular apps on your phone work this way.
A marketplace connects two groups and takes a cut of whatever passes between them. Uber takes a slice of your fare.
Ads mean users pay nothing and advertisers pay for their attention.
Usage-based means people pay for what they actually use, which is how most AI tools charge you.
For a first app you're realistically looking at the first three. The others need either enormous scale or two different groups of people showing up at the same time, and you won't have either in month one.
The number nobody mentions
Say you want $10,000 a month, which seems like a reasonable thing to want. Your app costs $5 a month, so you need 2,000 subscribers.
Here's where it gets awkward. Most apps convert somewhere between 2 and 5 percent of their free users into paying ones. So finding 2,000 payers means roughly 40,000 to 100,000 people need to discover your app, install it, and stick around long enough to care.
Finding a hundred thousand strangers is a much harder problem than writing the code, and it's the one almost nobody plans for.
Flip it around. Sell to businesses at $200 a month and that same $10,000 needs 50 customers. Fifty. That's a number you could genuinely reach by having conversations with people.
I'm not pushing you toward businesses. I just think most people pick one of these games without noticing there was a choice, and then wonder why theirs feels impossible.
What follows from the choice
Once you've picked, some things stop being opinions.
| If you chose | You live or die by |
|---|---|
| Consumer subscription | People not cancelling. Small price, enormous numbers |
| One-time purchase | A constant supply of new buyers. Every month restarts at zero |
| Freemium | Free users staying cheap to serve, and a few of them converting |
| Selling to businesses | A handful of relationships. Slow to sell, much bigger cheques |
Consumer subscription is the one most first-timers reach for, because it's what they see on their own phone every day. It also happens to need the most people of any option on that list. That doesn't make it wrong. It's just worth knowing which mountain you've decided to climb.
The sentence worth having
Somewhere before you write code, it helps to be able to finish this:
[Who] pays me [how much] [how often] for [what].
If the blanks won't fill in yet, that's fine. It usually means you have a project rather than a business, and there's nothing wrong with a project. Plenty of good things start as one. It's just useful to know which you're doing, because the two need completely different amounts of your life.
A quick story. When I started building my own things, the change that actually moved the needle wasn't technical at all. I stopped asking what would be cool to build and started asking whose problem I was solving, and whether it annoyed them enough to pay for it to stop.
Written down that sounds obvious. It wasn't obvious to me at the time, and I wasted a fair bit of effort before it clicked. The odd side effect was that it made me better at the work generally, because you stop guessing at what people want and start listening. Putting something out into the world and having a stranger pay for it teaches you things that building alone in a room never does.
If you want to try it on your own idea
There's nothing to do here. But if you have an idea rattling around and want a sanity check on the money side, this is a reasonable place to start.
That last line does more than it looks like it should. Ask for honesty and you get a genuinely useful answer. Leave it out and you tend to get a cheerleader.