Five apps making real money in niches most people walked right past. Revenue numbers are third-party estimates.
👋🏼 I'm Eldar - solo app builder, 8 iOS apps shipped, 2x Google DeepMind hackathon winner.
Every week I get the same DM: "can you build my app?"
Today I'm opening 4 slots. One offer, one price, one week. If I don't ship in 7 days, you get your money back.
Reply or check here to claim a slot: https://www.mados.ai/build
1. The Catholic prayer app pulling $4M/mo
Hallow: Prayer & Meditation · ~$4M/mo revenue · ~200K downloads · 4.89★ · Dec 2018
Hallow is a Catholic prayer app — guided audio prayers, scripture, meditations, daily reflections, and Bible-in-a-year programs. Mark Wahlberg shows up. Chris Pratt shows up. Famous Catholic athletes and bishops record prayer sessions. It's Calm for Catholics, except the audience pays differently.
Why it works: faith is one of the highest-retention categories in the App Store. People don't churn from a daily prayer habit. ~$20/dl ARPU at 200K downloads/month tells you the lifetime value here is real — Catholics will subscribe for years. The big incumbents are Bible widgets and YouVersion. Hallow took the harder angle (audio + community) and the audience showed up.
The insight: "prayer" looks crowded from the outside (5,000+ apps). But denominational prayer for a specific community is wide open. Catholic gets Hallow ($4M/mo). Muslim gets Pray ($1M+/mo). Most other faiths and denominations have nothing comparable. Pick a community, not the category.
What you could build:
"Daven" — guided audio Jewish prayer + Torah study app. Daily Shacharit/Mincha/Maariv with audio guides, Tehillim with English transliteration, parsha-of-the-week reflections. The Jewish community has zero high-quality, premium prayer apps despite massive willingness to pay.
"Salat" — Islamic prayer companion with audio Quran, daily Hadith reflections, guided dhikr meditations, and Ramadan/Hajj programs. Pray.com is the only player at scale, and it's still mostly text. Audio-first Islamic prayer is wide open.
"Sabbath" — guided audio app for Seventh-day Adventists, Mormons, or Evangelicals. Each denomination has 5-15M+ practitioners and zero premium, audio-first apps. Pick one, build deep, charge $80/year. Same playbook Hallow used for Catholics.
2. The astrology app that nobody talks about
CHANI: Your Astrology Guide · ~$500K/mo revenue · ~20K downloads · 4.92★ · Dec 2020
CHANI is a personalized astrology app from Chani Nicholas (a working astrologer with a real following). Daily readings based on your full birth chart, transit forecasts, ritual prompts, meditations, and a community feed. No "you'll meet a stranger today" garbage — this is astrology written for people who already take it seriously.
$500K/mo from only 20K downloads/month. That's $25/dl. CHANI users aren't curious — they're devoted. Co-Star ($400K/mo) gets the casual user with witty push notifications. CHANI gets the deep user with charts, books, and rituals. Both businesses, very different play.
The insight: astrology is one of the most resilient "belief" categories. The audience grew massively post-2020 (Gen Z especially), and the spend per user is astronomical because it's tied to identity, not novelty. Bible widgets and tarot are the obvious adjacent plays — but the underexplored space is taking astrology mechanics and applying them to specific moments (planning, relationships, health).
What you could build:
"MoonCycle" — period tracker with full astrological overlay. Stardust is already doing $400K/mo on this exact angle. The app maps your cycle to lunar phases, your sign, and your transits. The pitch isn't "track your period" — it's "understand your cycle in cosmic context." Same product as Flo, totally different audience.
"Synastry" — relationship compatibility based on full birth chart synastry, not just sun signs. Couples can sync, see daily compatibility scores, get prompts for tough days. Charge per couple. The astrology + couples crossover (CHANI + Candle from earlier editions) is a beautiful unmet need.
"Natal" — astrology for kids. Parents enter their kid's birth time and get personality insights, learning style guidance, and "what to expect this year" forecasts. Astrology-curious millennial moms are the most underserved audience in the App Store. They will pay anything for tools about their children.
3. Dog training as a SaaS
Woofz - Puppy and Dog Training · ~$300K/mo revenue · ~80K downloads · 4.58★ · Nov 2020
Woofz is a dog training app. You select your dog's age, breed, and current behavior issues, and it builds a personalized training program. Step-by-step lessons, video demonstrations, breed-specific tips, ultrasonic whistle, AI dog-emotion translator (yes really), and behavior tracking. It's Duolingo for puppies.
Pet apps are one of the most under-monetized categories on the App Store. Americans spend $150B/yr on pets — but the App Store revenue from pet apps is laughably small relative to that spend. Woofz is one of the few that figured out the unlock: position training as a course, not a tool. Course pricing → premium ARPU.
Why it works: new dog owner = peak desperation moment. They got the puppy, the puppy is destroying everything, and they need help NOW. They won't read a book. They won't watch a 40-minute YouTube video. They'll download an app and pay $40 if it solves the immediate problem. Same buying psychology as parenting apps and language apps.
What you could build:
"Kitten Academy" — same playbook for cats. Litter training, scratching post training, introducing new pets, dealing with aggression, indoor enrichment. Cat owners are 30% of US households and have basically zero apps targeting them. The ones that exist are all basic translators and games.
"Reactive Dog" — niche app for owners of reactive/anxious/aggressive dogs. Most dog training apps assume a normal puppy. The 20% of dogs with serious behavior issues is its own market with massive pain and willingness to pay. Charge $20/mo. Solve one specific problem deeply.
"PetPal AI" — AI vet triage app. Owner describes symptoms, uploads a photo, gets a probability list of conditions and "vet now / wait and see / monitor" guidance. Vet visits cost $200-500. An app that helps you decide when to actually go is worth $10/mo to every dog owner.
4. The visual planner built for ADHD brains
Tiimo: To-Do List & AI Planner · ~$200K/mo revenue · ~70K downloads · 4.57★ · Oct 2019
Tiimo is a visual day planner designed specifically for neurodivergent users — ADHD, autism, executive dysfunction. Time is shown as colored blocks on a circular or linear timeline (not a list of text). Big icons, gentle reminders, optional pomodoro, body-double mode, AI plan generator, and routines you can reuse.
Why it works: ADHD productivity is its own subgenre and the audience is huge — 1 in 9 US adults has ADHD by latest CDC stats, and another massive chunk self-identify (correctly or not) on TikTok. Generic productivity apps (Todoist, Notion, Things) actively fail this audience. They're text-heavy, decision-heavy, and assume you can already plan your day. Tiimo's whole pitch is "we built this for the brain that can't."
Tiimo charges ~$60/yr. With ~70K downloads/month they're at $200K/mo and growing. The bigger story: Structured ($200K/mo) and Sunsama (web) are taking the same audience with different angles. "Built for ADHD" is becoming a category, not a feature.
What you could build:
"BodyDouble" — virtual coworking app where ADHD users sit on a video call with strangers (or AI avatars) and just... work. Focusmate proved this works on web ($30/mo subscriptions). On iOS, basically nobody is doing it well. The pitch is "can't focus alone? sit with someone." Pure simple loop.
"Routine" — for ADHD parents managing kids' routines. Visual morning/bedtime checklists for kids that the parent customizes once and the kid follows. Sticker rewards, voice prompts, photos of the actual mess ("is your room like this picture?"). $15/mo to a parent who's losing her mind every morning is a no-brainer.
"DopaList" — to-do list with dopamine-tuned mechanics. Each task you complete triggers haptic, animation, and a little gamified streak. Built around the ADHD reality that the reward has to be immediate and visceral, not delayed. Sounds silly, will print money.
5. "What would I look like with bangs?" as a $400K/mo app
Cosmo: AI Editor, Hair Filters · ~$400K/mo revenue · ~200K downloads · 4.35★ · Jan 2023
Cosmo is an AI hairstyle try-on app. Upload a selfie, see yourself with 100+ different cuts and colors — bob, pixie, balayage, bangs, blonde, copper, full transformation. Plus AI photo editing (background swap, retouching, outfit changes). Built for the "about to book a hair appointment, terrified to commit" moment.
Why it works: this is the perfect organic content app. The before/after is the marketing. Every TikTok of "using AI to test 10 haircuts before my appointment" is a 100K-view video that converts at insane rates. HairApp ($300K/mo), Glowify ($200K/mo), and FaceLab ($300K/mo) are all competing for the same hook with different angles.
The deeper insight: "AI photo editor" is over. "AI photo editor for one specific decision" is the wave. Hair (Cosmo). Outfit (multiple apps). Photoshoot (Pose, from Edition 2). Headshot (multiple). Makeup. Tattoo placement. Each one extracts $5-10/dl by being the best at one thing instead of mediocre at everything.
What you could build:
"InkPreview" — AI tattoo placement on your own body. Upload a photo, place any design (or generate one from prompt), see how it looks on your arm/back/leg. Tattoo regret is a $1B+ removal industry — try-before-you-ink is a huge market. Partner with tattoo artists for revenue share.
"BeardLab" — AI beard try-on for men. 50 beard styles, see yourself before committing, get grooming product recommendations. Men buy aesthetic apps if you frame it as confidence/discipline. Frame it as "masculine grooming OS," not "hair filters."
"StyleMe" — AI outfit try-on using your own clothes. Take photos of items in your closet, AI generates outfits, you see yourself wearing them. The closet-to-outfit problem is universal and somehow nobody has nailed it. Higher repeat usage than haircuts because you outfit yourself every day.
These are real apps making real money right now. The niches aren't random — each one solves a specific problem someone desperately needed fixed. That's always where the opportunity is.
But spotting the idea is the easy part. Finding the right niche, validating it, actually shipping — that's where most people get stuck.
If you've got an idea but no time to build it — I'll ship it for you.
Rapid MVP — native iOS app, payments wired, on the App Store. 1 week. $3,000. Money back if I miss the deadline.
Only 4 slots open. First come, first served.
Claim a slot →See you next Thursday.
— Eldar