“Cross promotion helps with our existing app because we already have an audience and the use case translates so we were able to target folks at night for example that's something you don't have the first time around.”

Cross-promoting to existing audience is the unfair advantage when launching a second product

When launching sleep app Rest, Siniawski tapped Podcast App's existing users — specifically those who used the app at night, a behavioral signal of sleep use-case fit. This cross-promotion blast gave the zero-to-one phase a boost unavailable to a first-time founder. Even 130K subscribers is a meaningful launch advantage when they're the right audience for what you're building next.