Kadoink
Ring up to nine people at once by phone, SMS, or a link—no app or login needed.
What is Kadoink?
Kadoink helps you assemble groups for real-time calls and mass communication. It can ring up to nine phones simultaneously and reach people through direct phone and SMS channels or shareable push links. Recipients can join without downloading an app or creating an account, making it useful for quickly coordinating groups.
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FounderPlaybooks.
What other founders did to grow.
2722 dispatches from hundreds of founders, pulled from the week's best podcasts.
Authentication honestly isn't even needed for modern apps. Like mine doesn't have authentication or a database and I'm printing money. The reason I made it this way is for two reasons. I wanted to reduce friction as much as possible. I don't want my users wasting time on signing up.
Skip authentication and databases to eliminate mobile onboarding friction
By storing everything on-device and skipping sign-up, Matt removes the single most common drop-off point in mobile onboarding. The app anchors retention through daily prayer streaks and Bible verse rewards — habit loops that don't require accounts. This design choice also drove a 12% review rate, far above the typical 1-3%, since frictionless users who complete prayers are more satisfied and more likely to leave feedback.
I have a clear image of how my app could look like so that I could fairly say that it's objectively better than my competitors
Build Only What You Can Claim Is Objectively Better Than Competitors on UX
Ericas starts every new app by auditing competitors, noting what he likes and dislikes about their experience. His goal before writing a line of code is to arrive at a clear design vision he can objectively claim is better. This focused benchmark — not feature parity — defines the minimum he ships.
There's a play for whatever you're stuck on.
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