There isn't one. It's free, with no account and no sign-up. It's a personal project, shared as is, so it may not be perfect. Have fun making your lists.
Where do my notes go?
Nowhere. They stay on your phone, inside the app. Nothing is uploaded or synced, so they're private, and they're yours to look after.
How do I get it?
Open this page on your phone and tap Get FindNotes. The app walks you through adding it to your home screen.
What if I lose my phone?
Your notes go with it, unless you've made a backup. Export from Settings every so often and keep the file somewhere safe.
Is it finished?
Almost. Everything works, and it's used every day, so expect a few changes along the way. See what's new.