
Railway
Render
Vercel
Heroku
Render UIKit
Netlify
Coolify
Edge computing is the new frontier.

Substack
Formo.so
Advanced analytics for Substack writers. Runs 100% locally, no cloud, no subscription. Discover your superfans, churn risk, and cohort retention.

Which is more popular?
Based on our record, Fly.io seems to be a lot more popular than StackStats.app. While we know about 484 links to Fly.io, we've tracked only 1 mention of StackStats.app.
Website, pricing, platforms and company facts side by side.
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| Website | fly.io | stackstats.app |
| Pricing | ||
| Company | Startup from the United States | Startup from the United Arab Emirates · 1 - 9 employees · 2026 |
| Listed in |
In their own words, as submitted to SaaSHub.


No description of Fly.io yet.
StackStats is a local desktop app for serious Substack writers. Import your CSV exports and get analytics Substack doesn't show you: bot-filtered open rates, cohort retention, dead subscriber detection, superfan ID, content-to-growth correlation, and an optional AI layer (supports Ollama,...
What each product offers, as listed by its team.


Possible disadvantages
An editorial look at what each product does well and who it suits.


Overall verdict
Why this product is good
Recommended for
Overall verdict
Why this product is good
Recommended for
Walkthroughs and reviews on video.
We FLY a SPACESHIP! Video Game FLY.io Computer App with HobbyKidsTV
No StackStats.app videos yet. You could help us improve this page by suggesting one.
How often each product is chosen within a category, 0–100% relative to the other.


As answered by people managing Fly.io and StackStats.app.
StackStats.app's answer:
I built StackStats because Substack's native analytics weren't cutting it. I wanted cohort data, real open rates (not bot-inflated), and a way to identify which posts were actually driving subscriber growth — but every tool I found was either cloud-based or required migrating off Substack entirely. So I built a local app that works with Substack's own CSV exports. No migration, no cloud, no subscription.
StackStats.app's answer:
StackStats runs 100% locally on your machine — your subscriber data never touches a server. It also goes far beyond what Substack shows natively: bot-filtered open rates, cohort retention, superfan identification, dead subscriber detection, and content-to-growth correlation. No subscription, no account, no cloud. Pay once, own it forever.
StackStats.app's answer:
Most newsletter analytics tools are cloud-based SaaS with monthly subscriptions. StackStats is a one-time purchase that runs entirely on your device. For Substack writers who care about privacy — especially those with paid subscribers — that's a meaningful difference. You also get analytics features that don't exist anywhere else, like bot-filtered open rates and cohort retention, without having to migrate away from Substack.
StackStats.app's answer:
Serious Substack writers who are frustrated by Substack's shallow native analytics and want real data to drive growth — without moving their subscriber data to the cloud.
StackStats.app's answer:
Electron (macOS + Windows), HTML/CSS/JavaScript, Chart.js, PapaParse. Optional AI layer supports Ollama, Claude, GPT-4, Gemini, Groq, and OpenRouter. Licensing via Cloudflare Workers + D1. Payments via Gumroad.
Share your experience with using Fly.io and StackStats.app. For example, how are they different and which one is better?
External articles and on-site reviews we used to compare the two products.


Yes! Several platforms offer real free tiers in 2026. SnapDeploy gives you free containers (no time limits) with no credit card required — and your hours only count when your app is running. Render offers free web...
Fly.io is one the best free alternatives to Heroku that you can use. It’s designed for developers and students to run small applications for free and scale costs affordably as you grow. Just like Heroku it comes with...
We have no reviews of StackStats.app yet. Be the first one to post
Recommendations tracked on public social media and blogs since March 2021.


Tool What it is Official link Cloudflare Workers Edge runtime + Durable Objects - the supported Deploy migration target Https://workers.cloudflare.com {/* MONETIZATION NOTE: official URL above; Cloudflare's affiliate terms were... - Source: dev.to / 25 days ago
Go 1.26 standard library, modernc.org/sqlite for a pure Go SQLite, and solana-go for the RPC client, transaction building and the SPL Memo instruction. React 19, Vite 8, TypeScript 7 and Tailwind CSS 4 on the page. Alegreya and IBM Plex,... - Source: dev.to / 2 months ago
Fly.io opens up two things Heroku keeps at arm's length: real multi-region deployment and full control over the runtime. Heroku's Common Runtime offers two regions (US and EU), and Private Spaces gets you one region at a time from a... - Source: dev.to / 4 months ago
I'm working on 3 products now: 1. FormBeep(https://formbeep.com) at $38 MRR now - A form to Whatsapp tool. Stack is mainly CF workers with Clerk Auth. 2. SlashLink(https://slashlink.app) $0 - A simple pay as you go amazon link localizer.... - Source: Hacker News / 3 days ago
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Agile deployment platform for Ruby, Node.js, Clojure, Java, Python, and Scala. Setup takes only minutes and deploys are instant through git. Leave tedious server maintenance to Heroku and focus on your code.
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