I'm starting work on a simple todo app designed to solve a major friction point I see in existing apps. I don't believe todo apps should require authentication or permission hoopla to build a basic list of things to do.    So I'm going to build a simple authless, permissionless app that will allow users to build adhoc lists and start checking off items in under 30 seconds. Once you start a list, a unique URL is generated as you create your first item. Anyone with that URL can then contribute to adding items or checking off items.    It's dead simple but if I think use cases, I think alternatives are just too much work for the payoff. Let's say you want to host a last-minute dinner party and have people pick up a few items. Are you really going to start a Trello board, create a bunch of tasks...then have to worry about inviting everyone and expecting them to create accounts? It would be better if you just send an email and paste a link to the shared todo list. From there, everyone is 1 click away from contributing.    What do you think? Is there a good reason not to go authless or should I keep anything in mind as I build?