TL;DR: It is definitely there on the mobile app, you just gotta look right above the checkout button for the tiny Invite others to shop link. I had to use this feature recently when I was spec-ing out a new server rack with some coworkers. We were looking at some high-end stuff like the Ubiquiti Dream Machine Pro and a bunch of rack-mount shelves. Doing that via copy-pasting links is a total nightmare, but the collaborative cart worked so well for us. Honestly, I've been really satisfied with how it handles the real-time updates. No complaints from me at all. To get it working on your phone, open the Amazon app, hit the cart icon, and look just above the big Proceed to Checkout button. There is a little text link that says Invite others to shop. Tapping that creates a unique session link you can text to your cousins. I was worried it might be buggy or lose items, but we had five people adding things simultaneously and it didnt drop a single SKU. Ngl, it is way more convenient than the desktop version once you actually find where they hid the button. My brain was also fried the first time I looked for it, so dont feel bad. It works great for stuff like those BearVault canisters too since everyone can see if someone already added one. Basically makes the logistics way smoother.

Its definitely on the mobile app and works fantastic! Just saw a post on Smartphone Board about how it's basically a hidden power feature now.

• Cart Share: Amazing for data accuracy and real-time inventory specs.
• Shared Lists: Better for asynchronous planning, though it lacks the direct checkout speed. Go with the cart link! It's way more efficient for getting those bear canisters ordered by tonight.

Just caught your post and man, I totally get the stress... PNW trips are amazing but the logistics are a nightmare. I used the feature recently for a climbing trip. It definitely exists on the mobile app, but it's kinda tucked away at the top of the cart page. Just look for the invite others text right near your subtotal. One thing I would say is to be super careful with the shared cart because prices on stuff like bear canisters can jump around hourly. I'd suggest checking out some tips on amazon cart share before you send the link out because if someone adds a version of a product from a third-party seller, your shipping might get all messed up. I almost paid like twenty bucks extra for shipping once because a friend picked a similar item that wasnt Prime eligible. Also, just a heads up... make sure your cousins know they're just adding items and not to hit the buy now button by mistake, or you're gonna have a mess of individual packages arriving at different times. If you're buying bulk snacks, watch the weight too because sometimes the free shipping has hidden thresholds for heavy items. Just keep an eye on that final total before you click pay tonight. Hope you guys have an awesome time in the woods!