How Robinhood got its users

Give every user a real URL, not a tracking parameter. Robinhood's invite is join.robinhood.com/tjb35: a short second-level domain, the user's handle as the path, and a page that renders in full for someone with no account and no cookie. It is short enough to type from memory and say out loud in a voice note. Buy or subdomain something short, mint one permanent path per user at signup, and serve that page to logged-out visitors.

done whenOpen your own invite link in a private window on your phone. If you hit a login wall, a 404, an app store redirect, or a URL you could not read aloud without spelling out a random string, you do not have an artifact yet.

Put the recipient's half of the reward first and make the sender's half automatic. The page says 'Your gift stock is waiting for you' and the button says 'Claim your gift stock now'. The sender's name appears as a co-beneficiary ('You and Thomas James can both get a gift'), never as someone asking for a favor. Write your invite page so a stranger reads it as a thing they already own, and so the sender never has to explain what they get out of it.

done whenRead your invite page out loud as the recipient and count the words describing what they get before the first word describing what the sender gets. If the sender's benefit comes first, or if the page needs the sender to add a caption explaining it, rewrite it.

Publish the real odds on the page instead of hiding behind 'up to'. Robinhood prints the whole distribution: $5 to $200, 1 in 100 get at least $20, 1 in 1000 get at least $50, and 98% land between $5 and $10. Stating the boring likely outcome is what lets a normal person send the link to a coworker without feeling like a shill. Write your actual numbers on the page and keep them there.

done whenWrite the most likely outcome of your reward as one plain sentence and put it on the page. If seeing that sentence in writing makes you want to delete the offer, the reward is too thin to be sent by anyone.

File the invite as an earnings surface, not a settings row. In the app it is 'Earn stock' then 'Invite contacts'; on the web it is 'Rewards' then 'Share link'. The user goes there to collect something and finds the link waiting, instead of hunting for a share option under Account. Name your surface after what the user gets, and reach it in two taps from the first screen.

done whenCount taps from your app's first screen to a copyable invite link. More than two taps, or a home under Settings, Account, or Help, means it is filed as admin and will not be found.

Gate the reward behind the exact step that turns a recipient into a sender. Robinhood pays nothing on click: the new person signs up, links a bank, then picks their stock, with 60 days before the offer expires and a 3 trading day hold before selling. By the time the reward lands they have completed the setup that makes their own join link worth sending. Move your payout to sit just after your activation step, and drop the new user on their own invite page the moment it clears.

done whenTrace every step between a stranger clicking your link and that stranger being able to send their own. If the reward arrives before they have done the one thing you would call activation, the chain stops at one hop.