Vertical scrolling is a much less tedious interaction than pinching and zooming back and forth to different sections of a 2D plane.

On the other hand, the spatial benefits to such a plane helps people remember where to look if they want to return to a section, whereas with endless scrolling, it's nearly impossible to find something you saw before until you happen upon it again scrolling back up for an indeterminate amount of time.

This makes me think it would be useful for mobile browsers to allow adding temporary scroll bookmarks while using a page. It'd be useful for browsing lots of items, restaurant menus, on a single page, etc.

("that looks good" [bookmark scroll position] ... [keep scrolling] ... [tap icon to return to the previously saved position])

I genuinely think scrolling is more tedious. Have you visited any of apple's product pages lately? Makes me yarf.

EDIT: At least restaurant menu sites aren't that bad yet. Can you imagine? "Hamburger. Redefined." <SCROLLS> Hamburger slowly pieces together across the screen tied to your scrolling. "We think you're gonna love it." <SCROLLS> Pickles slowly fade in and out to demonstrate the difference between Hamburger and Hamburger Pro

Scrolling itself isn't tedious compared to panning and zooming a PDF. The information density is what's important. If you have to do a bunch of scrolling to see just a few items then, yes, they failed.

It depends what the PDF is. Reading a PDF book is tedious because you're endlessly panning back and forth at every line. But you don't read a restaurant menu from start to finish like that so it makes sense to have a less linear way of navigating than scrolling.

> Scrolling itself isn't tedious compared to panning and zooming a PDF.

I simply disagree, and think the EXACT opposite.

Panning and Zooming a two-dimensional, immutable file itself isn't tedious compared to scrolling.

(You're straw-manning PDFs, though it could be any 2D image or mutable document file)

> "it would be useful for mobile browsers to allow adding temporary scroll bookmarks while using a page"

This shouldn't be necessary with a well-designed menu interface. Firstly the whole thing should be indexed anyway, allowing easy jumping between categories. And if something looks good you should be able to favourite it with a single tap, or at least add it to your order with a single tap. (If you end up with too many items in you order, consider it a short-list, reviewing the items and narrowing it down from the final order review page).

I'm thinking more in terms of browsing, not just selectable items in a menu, but any scrollable content.

A real-world analog would be adhesive color tabs people stick to the sides of books or printed documents to mark a paragraph non-destructively, so they can return to that point later more easily.

Think anchor headings, except user-driven, because many websites don't even use anchors to enable linking to page sections by URL hashes, and without inspecting headings for anchors (by tapping or long-pressing on them), nobody would ever know it's a feature.

I wish I could just mark my current scroll position and return to it later by navigating back + forth between the ones I've saved for a page. I've lost count how many times I've made mental notes saying "This is interesting, I'll return to this bit later" only to struggle finding it again because it's lost in a sea of text. Browsers have no way to temporarily bookmark bits of content without developers (or CMS'es) being smart enough to anchor headings and sections.

Indexing is INHERENT to a 2D document/file. It doesn't need to be indexed or categories. It can hold ALL the information you want to peruse and compare in a given moment. You just, simply look around and view it! - willy wonka

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