How One TikTok Video Brought 100,000 Users

## Hello! Who are you and what business did you start?

Hey there! I’m Kyan Santiago-Calling. I am a 21-year-old computer science student at San Diego State University (SDSU), an indie hacker, and the founder of ToneAdapt.

ToneAdapt is an AI guitar-tone matching app. If you play guitar, you know the struggle: you look up a YouTube video to learn a famous song, but the teacher is playing a $3,000 guitar through a huge, vintage amp. If you try their settings on your cheap bedroom amp, it sounds terrible.

ToneAdapt fixes that. You pick a famous song, enter the exact gear you own, and our app tells you exactly how to set your knobs to get that perfect sound. It acts as a translator between the famous gear and your personal gear.

I launched the first version in early 2025. Today, we have over 100,000 registered users. The business is doing about $25,000 a month in total revenue, and we recently hit the #1 spot in the guitar niche on the App Store.

What's your backstory and how did you come up with the idea?

Every great product starts with a founder solving their own problem. I am a guitarist, and I was so frustrated with "tone chasing." I spent more time twisting knobs on my amp than actually playing the guitar.

There was no tool that took my actual gear into account. So, the idea was born entirely from my own pain. I didn't do any big market research or send out surveys. My validation was simply: I need this to exist, so other guitarists probably do too.

At the time, I just wanted to build a neat portfolio project for my resume to help me get a software engineering internship. I had no idea it would turn into a real business.

Take us through the process of building the first version of ToneAdapt.

I built the first version very fast. I didn't spend months planning.

I used Next.js for the website, Supabase for my database and logins, and Stripe to take payments. The hardest part was the data. I gathered public info from rig-rundowns, guitar forums, and artist interviews to build a database of over 2,000 guitars and 1,500 amps.

Then, I used light AI models to do the math. The AI figures out the difference between a loud, dark pickup and a bright, quiet pickup, and adjusts the amp settings to match.

The first version was very rough. But I followed the golden rule of indie hacking: launch early and fix it later.

Describe the process of launching the business and getting your first customers.

I didn't have a marketing budget or an email list. I got my very first users from three free channels:

1. Twitter "Build in Public": I started sharing my journey on X (Twitter) under the handle @kyanbuilds. I posted raw screenshots of my code and my revenue. My first paying customers were literally just my Twitter followers who wanted to support me.

2. Reddit Forums: I went to places like the /r/guitar subreddit and shared my tool for free. People loved it and started using it right away.

3. TikTok Virality: This was the rocket fuel. Because I built this for myself, I just recorded my phone screen showing how the app worked, slapped some text on it, and posted it to TikTok. I went to sleep, and when I woke up, the video had over 1 million views.

On May 12th, 2026, I tweeted: " $1,000 before 12 pm today 🙏 My life is turning upside down bc of this dumb little app I made for a problem I had."

That one tweet, combined with the TikTok traffic, drove thousands of users to my site in a single weekend.

How did you grow the app to 100,000 users? What is your strategy?

My growth engine is 100% focused on short-form video. We don't just have a product; we own the distribution channel. Here is how we get users:

• Making the Product the Ad: I post 2 to 3 short videos a day on TikTok and Instagram Reels. The hook is always: "Want the Metallica tone with YOUR gear?" Then I show a quick demo of the app giving the settings, and I play the riff to prove it works.

• App Store SEO (ASO): When I launched the iOS app, I made sure to use keywords like "guitar tone match" and "amp settings." Having a 4.8-star rating and the social proof of "100k+ users" makes people download it instantly.

• Paid Ads on Winners: I didn't know how to run ads at first. But once a TikTok video went viral organically, I started putting money behind it to run it as a paid ad.

• Community: We built a Discord server where users share the tones they created. It keeps people coming back. Every time someone matches a tone, they can tap "Share" to post it on social media, which acts as a free ad for us.

How does the business make money? Let's talk about revenue.

ToneAdapt runs on a "freemium" model. There is zero friction to start. You can download the app and do a basic tone match for free. This gets them hooked.

Once they see the magic, they hit a paywall for premium features, like unlimited matches and saving presets. Here is how our $25,000/month breaks down:

1. Subscriptions (70%): We charge $6.99/week, $14.99/month, or $59.99/year. The trial-to-paid conversion rate is very high.

2. Lifetime Access (20%): We offer a one-time payment for hobbyists who hate subscriptions.

3. Consulting (10%): Because of my Twitter following, I also make money helping other people build their apps.

What were your biggest mistakes or challenges?

1. Reinventing the Wheel: I actually advise people not to do what I did. Building something completely new with a massive database was very hard. It is usually much safer to copy a proven business model and just market it better. I took a big risk, but thankfully, it paid off because guitarists really needed this.

2. Angry Forums: Early on, someone on the MarshallForum made a thread called "Pure Ragebait." They were mad because my app didn't have obscure amps like the Marshall 2203 yet, and called it a toy for "noobs." Instead of getting upset, I replied nicely and spent the next week adding all their requested amps to the database.

3. Scaling the Tech: When we hit 100,000 users, the app started to slow down. I had to quickly rewrite parts of the backend so the app wouldn't crash.

What is the "Secret Sauce" that made ToneAdapt win?

If I had to break it down, it's four things:

• Zero Friction: No login required to try it. People want to see the value immediately.

• The "Aha!" Moment: Guitar tone is visual and auditory. It makes for perfect social media content.

• Personal Branding: Being a 21-year-old student building in public made people root for me.

• Content is Distribution: I didn't need a marketing team. Short-form video on TikTok and Reels is a cheat code if you post consistently.

What platform/tools do you use for your business?

• Stack: Next.js, Supabase (Database/Auth), native iOS (Swift)

• AI: Custom matching logic + OpenAI

• Payments: Stripe & Apple App Store

• Hosting: Vercel

What does the future look like?

With the business highly profitable, I want to expand. I am looking at building a desktop app for Mac/Windows that plugs directly into recording software (DAWs). I also want to add Bass and Keyboard support, and maybe let users sell their own premium tone packs inside the app.

What advice do you have for other entrepreneurs?

Scratch your own itch. Build something you desperately want to use.

Don't wait to launch. Ship the ugly version today, post a video of it on TikTok, and see if people care. In 2026, the tools are so good that a solo college kid can build an app in a weekend. If you have a real problem and you share your journey online, your "$1,000-before-noon" moment might be closer than you think.