One Button Replaced My Entire Signup Flow. Here's What 16 Days of Data Showed.

I spent 9.5 months watching my app collect ghost accounts. Users who filled out the registration form, picked a password, hit submit, and then vanished. Never verified their email. Never came back.

One hundred and twenty-two people did this. Out of 450 total signups, 27% just disappeared at the inbox step.

Then I added one button. Apple Sign In. No form, no password, no verification email. Just one tap and Face ID.

Sixteen days later, 204 new users had signed up. That's more than I got from email in the first four months combined. And not a single one of those 204 chose the email option. Zero.

Here's what that looked like in practice.

450 Users in 9.5 Months (And 122 of Them Were Ghosts)

I built Deutschwunder as a free German language learning app. Quizzes, games, learning journeys, speech recognition. The whole thing works without an account. Thousands of people download it and use it every day without ever creating one.

But if you wanted to save your progress across devices, you needed an account. And for 9.5 months, that meant the classic flow: enter email, pick a password, submit, switch to your email app, find the verification link, click it, switch back to the app. Six steps minimum.

The result? About 47 signups per month. Not terrible for a free app with zero marketing budget. But here's the part that bothered me: of those 450 users, 122 never verified their email. They went through the effort of filling out the form, and then the verification email killed the momentum.

Twenty-seven percent. Just gone.

Industry data says 30% email verification drop-off is the benchmark. So my numbers weren't even unusual. That's the depressing part. This is just normal. Everyone building apps with email signup is silently losing a quarter of their signups, and most don't even realize it because they only see the users who made it through.

I tell my clients to optimize their funnels. I audit conversion paths for a living. And my own app had a 27% leak I'd been ignoring for nine months. Classic case of the tailor who can't sew his own pants.

Why I Finally Added Apple Sign In

The honest answer? Apple made me.

If your iOS app offers any form of third-party authentication, Apple requires you to also offer Sign In with Apple. It's in the App Store Review Guidelines. So when I was planning version 1.6.0, it was on the list.

But I'd been procrastinating. Not because the implementation is hard. It's actually straightforward. Apple handles the entire auth flow. You get a verified identity token, a confirmed email (or a relay address), and the user is ready to go. No password to hash, no verification email to send, no "check your spam folder" support tickets.

The whole thing is one tap and a Face ID confirmation. That's it.

I shipped it on May 16, 2026. And then I watched the numbers.

16 Days of Data That Made Me Feel Stupid

In the 16 days after launching Apple Sign In, 204 new users signed up. That's roughly 383 per month projected, compared to the 47 per month I was getting with email.

An 8x increase in signup velocity. No ads. No redesign. No new features. Just one button.

But the stat that really got me? Zero new email signups. Not "most chose Apple." Not "the majority preferred Apple." Zero. Every single new user chose Apple Sign In, even though the email option was still right there on the screen.

The industry says social login typically improves conversions by 20 to 60 percent. I got an 800% increase. I don't fully understand why the gap is so dramatic, but I have a theory: for a free language learning app on iOS, the overlap between "your users" and "people who trust Apple with their identity" is basically 100%. These aren't web users choosing between Google, Facebook, and email. These are iPhone owners who already use Face ID for everything.

Here's the before and after:

Metric	Email (9.5 months)	Apple Sign In (16 days)
Total signups	450	204
Monthly rate	~47	~383 (projected)
Daily rate	~1.5	~12.8
Verified/active	328 (73%)	204 (100%)
Dropped off	122 (27%)	0 (0%)

Every Apple user is immediately active. No verification step means no drop-off. The 27% leak? Gone.

The Weekend Pattern Nobody Talks About

When you look at the daily numbers, something interesting shows up.

Signups spike on weekends. Consistently. The peak days were Saturdays and Sundays, with mid-week dips. It makes sense when you think about it: people learn German in their free time. Nobody's opening a language learning app at 2 PM on a Tuesday between meetings.

This is a tiny data point, but it's the kind of thing you only see when you look at raw daily numbers instead of monthly averages. And it has practical implications. If I ever send push notifications, I should time them for Friday evenings. If I release new content, weekends are when people will actually engage with it. If I run any kind of promotion, Saturday morning is the window.

Small insight. Big difference in how you think about user engagement.

57% Chose "Hide My Email" (And That's Fine)

Here's something I didn't expect. More than half of the Apple Sign In users, 57%, chose Apple's "Hide My Email" feature. Instead of sharing their real email address, Apple generates a private relay address that forwards to their inbox.

That's 116 people who specifically opted to not give me their real email. And honestly? Good for them.

If I were a growth marketer, this would keep me up at night. You can't segment these users by email domain. You can't enrich their profiles with third-party data. You can't sell their email to anyone (not that I would, but plenty of apps do).

But I'm building a language learning app, not an email list. These users signed up. They're using the app. They're learning German. That's the whole point.

The bigger insight is this: these 116 people probably would never have created an account through the email form. They care about their privacy enough to use a built-in Apple feature to protect it. A traditional signup form wasn't just inconvenient for them. It was a dealbreaker.

Apple Sign In didn't just speed up signups. It unlocked an entire segment of users who were invisible to me before.

What the Numbers Actually Mean

Let me zoom out for a second.

Deutschwunder has thousands of active downloads. People use it every day without ever creating an account because the app provides genuine value without one. You can play games, take quizzes, go through learning journeys. All without signing up.

As I wrote about before, the philosophy has always been to give the value first. The account is optional. It's there for syncing progress and unlocking some features, but the core experience is free and open.

So when I say signups went from 47 to 383 per month, that's not about "converting" more users. It's about removing the barrier that was keeping interested users from taking a step they already wanted to take. The app didn't get better. The door just got easier to open.

This isn't about Apple Sign In being magic. It's about email signup being broken. Every field you add to a form, every "check your inbox" instruction, every "click the verification link" step is a user who decided it wasn't worth the effort. The Baymard Institute found that every form field beyond two costs you abandonment. My email signup had five steps minimum.

Just like when I got 1,300 visitors to WunderType with zero ad spend, the biggest growth lever wasn't adding something new. It was removing something that was in the way.

What I'd Tell Other Indie Developers

If you're building an iOS app and you haven't added Apple Sign In yet, stop reading and go do it. I'm not being hyperbolic. The data is overwhelming, not just mine, but across the industry. One developer on Reddit reported going from 1.8% to 30% conversion after adding one-click signup. Mine went up 8x.

Don't A/B test this. The signal is too strong. Just ship it.

A few things I learned during implementation:

Let users use your app without an account. Deutschwunder works fully without one. This means that when someone does create an account, they're already invested. They've already experienced the value. The signup isn't a gate, it's a choice.

Accept that 50%+ will hide their email. Build your engagement strategy around in-app communication, not email campaigns. Push notifications, in-app messages, feature discovery. Don't fight the privacy trend. Work with it.

Tag your auth providers correctly. I initially stored all users with a generic provider tag regardless of how they signed up. This made it impossible to segment the data later. I had to go back and use the external identifier field to distinguish Apple users. Save yourself the headache and get this right from day one.

Don't remove email signup yet. I considered it. With 100% of new signups choosing Apple, the data says I should. But some users might not have an Apple ID, or they might be testing on a simulator. Keep it as a fallback. Let the data keep building.

Sure, everyone's building an app now. The question is whether you're paying attention to the details that actually matter. The features are the easy part. The signup flow, the onboarding friction, the invisible 27% you're losing? That's where the real work is.

I spent 9.5 months ignoring a broken funnel in my own app while telling clients to fix theirs. One button, 16 days, 8x signups. Sometimes the experiment you've been putting off is the one that changes everything.

Need help thinking through your own app's onboarding friction? Let's talk about what's actually standing between your users and the door.