I rebuilt a $1B app and now make $14K/month

Dennis

• Self‑taught developer, former diplomat who learned coding in two months
• Built Yaphone, a browser‑based cheap international calling service
• Launched in March 2025, shortly after Microsoft announced Skype’s shutdown
• Grew to $14 k / month revenue and 10 k registered users in 7 months

Products and Offerings

• Core product: web dialer that lets users make/receive international calls for cents via VoIP
• Pay‑as‑you‑go credit model for individuals, travelers, expats, and businesses
• Enterprise plan added on the fly; 20 B2B clients, one paying ~$1 k / month

Metrics and Financials

• Month 1 revenue: $4 k; month 3: $10.8 k; month 6: $13.3 k; total $14 k / month now
• 4.5 k paying individual customers; 20 enterprise clients
• September usage: 27 k calls, with continuous active users on the site
• Main cost: Twilio (voice routing), ~35 % of monthly earnings

Strategy and Growth

• Identified a proven market: international calling, validated by Skype shutdown tweet
• Built MVP in a weekend using Next.js, React, HTML/CSS
• Launch tactic: Reddit posts with screenshots and concise copy; first sales within minutes
• Follow‑up: regular posts in entrepreneur subreddits, gaining 150 users in the first week
• SEO hack: contacted authors of high‑authority “Skype alternative” articles to replace mentions with Yaphone, driving organic traffic
• B2B expansion triggered by a night‑time inquiry; built enterprise plan overnight and secured a $1 k / month client
• Ongoing: daily outreach to paying customers for feedback, rapid iteration, and churn control

Tech Stack and Infrastructure

• Front‑end: Next.js (React) for fast development
• Coding assistance: Cursor AI tool for both code and copy
• Hosting: Vercel
• Payments: Stripe
• Voice service: Twilio
• SEO tools: Ahrefs for keyword research; careful sitemap configuration (including “www” prefix)

Lessons and Advice

• Target markets where incumbents are “dinosaurs” and slow to adapt
• Build a functional MVP quickly; design and core feature must work, perfection isn’t required
• Craft a compelling founder story to capture attention on platforms like Reddit
• Leverage timing around big news events to amplify virality
• Prioritize SEO from day 1 and be meticulous with technical details (e.g., sitemap prefixes)
• Directly contact high‑authority site owners to replace competitor mentions with your product
• Maintain personal contact with users for feedback and early issue detection
• Add a B2B layer early for larger contracts and lower churn.