How do I zap a specific note? 
Discussion
#asknostr
Apple didn't like zaps and forced Damus to hide the button. TestFlight builds can activate them via a certain script (search for "nostrscript" and you shall find it; I don't have the link with me right now), or you can use nostr:npub1wxl6njlcgygduct7jkgzrvyvd9fylj4pqvll6p32h59wyetm5fxqjchcan to zap people with a reaction.