Apps

Apps we've built

Real products built with the help of AI — proof of what's possible, and the source of a lot of the lessons shared in the guides and blog.

Credit utilization, tracked to the day
LimitKeep
LimitKeep tracks every card against its own statement closing date and tells you what to pay, and when, to report the number you actually want.
Next.jsSupabaseVercelBuilt with AI
Visit LimitKeep (opens in a new tab)
- Tracks each card's balance, limit and utilization
- Knows each card's statement closing and payment due dates
- Recommends how much to pay on which card before it reports
- Reminders before cards report and payments are due
Newsletters on your own domain
SPEN10 Mail
Private beta
SPEN10 Mail runs signup forms, broadcasts, automated sequences and an inbox for replies, with an AI writer that sounds like you. Every email goes out from your own domain, so your sending reputation is yours alone. It started as the autoresponder I built for my own SPEN10 list.
Next.jsSupabaseClaude APIVercelBuilt with AI
Join the waitlist (opens in a new tab)
- Sends from your own domain, so your reputation is yours alone
- Step-by-step DNS setup for your domain provider (coming soon)
- Drag-and-drop sequences with waits, conditions and branches
- Broadcasts with per-link click and unsubscribe reports
- Replies land in an inbox inside the app
- AI drafts in your voice; nothing sends until you press the button

More apps are in the works. Subscribe below to hear when the next one launches.