Poor Man's Back End-as-a-Service (BaaS), Similar to Firebase/Supabase/Pocketbase

Do we still need a back-end, now that Chrome supports the File System Access API on both desktop and mobile?

I have started writing web apps that simply store the user data as a file, and I am very pleased with this approach.

It works perfectly for Desktop and Android.

iOS does not allow for real Chrome everywhere (only in Europe, I think), so I also offer to store the data in the "Origin private file system" which all browsers support. Fortunately it has the same API, so implementing it was no additional work. Only downside is that it cannot put files in a user selected directory. So in that mode, I support a backup via an old-fashioned download link.

This way, users do not have to put their data into the cloud. It all stays on their own device.

What about those of us who use multiple devices, or multiple browsers? I've been using local storage for years and it's definitely hampering adoption, especially for multiplayer.

One approach might be to save the file to a shared drive like Google Drive?