Notes from the operator behind Cal AI.

Weekly insights on AI and scaling consumer apps from Jake Castillo.

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Newsletter Archive

Jul 11, 2026

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1 min read

The ULTIMATE apple ads giveaway

one email to rule them all

Jake Castillo

The ultimate cheat sheet: influencer marketing edition

Jun 23, 2026

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2 min read

The ultimate cheat sheet: influencer marketing edition

read this or blow your budget

Jake Castillo

7 underrated app k*llers you need to know

Jun 20, 2026

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3 min read

7 underrated app k*llers you need to know

bookmark this

Jake Castillo

Jun 13, 2026

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1 min read

Why we let Cal AI bleed $$$

profit was never the point (at first)

Jake Castillo

Why we paid every influencer 100% upfront

Jun 2, 2026

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1 min read

Why we paid every influencer 100% upfront

it almost broke us, but it was the right move

Jake Castillo

The 20-second influencer test that saved us millions

May 27, 2026

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1 min read

The 20-second influencer test that saved us millions

stop building a case for bad creators

Jake Castillo

ALL POSTS

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8 goated Grok Bot resources for ya

I'm hooked

Oct 31, 2026

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1 min read

I QUIT CAL AI

here's what that means for you (and me)

Oct 29, 2026

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2 min read

The ONLY 4 app metrics you should care about

most founders can't tell me all four

Oct 17, 2026

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2 min read

The rumors are true 👀 👀 👀

I need your help

Oct 10, 2026

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1 min read

How to become an app retention gangster

copy the ecom bros (seriously)

Oct 7, 2026

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3 min read