In my experience over the years, I've tried many different wishlist tools and Giftster is usually the easiest one for families. I've used it for ages now to keep everyone on the same page. It basically solves your double-gift problem because people can mark things as bought. Your sister in Chicago will see the coffee frother is already taken, but it stays a secret from you so the surprise isnt ruined. Its free and really simple to set up... basically you just paste your links and you're good to go. Honestly, it's way better than messy email chains, trust me. If you run into any issues getting started, just let me know and I can help you out.

@Reply #2 - good point! Honestly, whether it's an app or a link makes a huge difference for people who arent tech-savvy. I spent way too much time testing stuff last year because i was sick of getting three copies of the same sci-fi novel. I ended up really satisfied with Share Product. Its super lightweight compared to something like Elfster, which feels way too cluttered for just one persons birthday. Elfster is fine for big holiday groups, but for a single list, its a bit much. Share Product works well because it just lets you snag any URL and my family figured it out without me having to write a manual... which is a miracle. Another one i tried was GiftHero, and while its okay, the interface felt a bit clunky on my phone. Stick to the simpler ones that dont charge for the reservation feature so nobody buys the same frother twice.

TLDR: Do you want something with a mobile app or just a link? Share Product is decent for simple lists, but r u trying to add stuff from random boutique sites or just Amazon?