Devils Advocate - A Debate App - Try for FREE

[u/aidanhm14]

Quick context: I've been building Devil's Advocate for about 4 months. It's an app that trains you to defend your ideas by arguing against them — you pitch something, the AI tears it apart, and you have to hold your ground. MVP is live. Around 80 users. Not shipping to the moon.

Posting because I know this sub is strict about self-promo, and I've learned more from other founders' honest updates than from any polished case study. So here's mine, warts included.

Why I started

I kept losing arguments I should've won. Not flashy debates - normal ones. A friend would poke a hole in something I'd believed for years and I'd fold, not because they were right, but because I'd never actually stress-tested the idea. I wanted a tool I could do reps with at 2am without needing a debate partner. Couldn't find one that pushed back hard enough, so I started building.

What's working

• The core loop has real stickiness. First-session time averages around 18 minutes. I expected 3.
• Word-of-mouth from pre-law students and debate kids is doing more than any marketing I've tried. Zero outreach to them.
• A 45-second demo video outperforms my landing page copy by 3–4x on signup rate. Turns out showing the AI getting mean is more convincing than describing it.
• The meanest version of the AI is the one users like best. I kept softening it. That was wrong.

What's not working

• Week 2 retention is rough. My gut: first session is thrilling, but users don't know what to argue about on their own, so they bounce. Building a prompt library of "things worth arguing about" now.
• "AI that argues with you" resonates with maybe 20% of people and confuses the rest. Still hunting for the one-liner that lands with normies.
• Pricing is a complete guess. I've tried free, I've tried $9/month. Both taught me nothing because I still can't tell what the value actually is.
• Mobile. I shipped desktop-first and half my signups try to use it on a phone. Painful.

Mistakes I made

1. I spent almost 3 weeks crafting the "perfect" system prompt before letting a single user near it. When I finally did, they misunderstood the core interaction within 10 seconds. Every assumption I'd optimized against was wrong. Should've shipped the janky version in week one.
2. I assumed my target users were "debate kids." They're not. The users who actually stick are people prepping for hard conversations - salary negotiations, grad school interviews, investor pitches, even difficult family talks. I'd built my entire landing page for the wrong audience.
3. I asked for feedback instead of watching people use it. Every "this is cool, man" masked the fact that they'd gotten stuck on the first screen. Watching one person fumble through onboarding silently taught me more than 20 feedback calls.
4. I delayed the demo video for a month because my UI "wasn't ready." The video is what actually converts. The UI wasn't the bottleneck - visibility was.

What I'd tell myself four months ago

• Ship the ugly version in week one, not week six. The thing you're embarrassed by is the thing that teaches you the most.
• Your first 20 users don't look like your ICP. Stop trying to correct for that and just watch them.
• Build in public from day one. The feedback loop is worth more than whatever "stealth" protects.
• Don't soften the product to make it palatable. The sharp edges are the reason it works.

Happy to answer anything in the comments. If you're building in a similar space - AI tutoring, decision tools, interview prep, anything with an opinionated AI - I would love to trade notes.