Most document viewers were designed in 2012, shipped by 2014, and have been adjusted in the margins ever since. They have a sidebar of pages, a top toolbar of actions, a zoomable canvas in the middle, and a footer with a page count. They render PDFs at a fixed DPI and feel slow on mobile.
We had a chance to redesign the surface. Here's what we kept, what we changed, and what we threw out — and why most of the work was about removing rather than adding.
What we kept
- The canvas in the middle. The whole point is the document; the viewer should mostly be invisible.
- The keyboard shortcuts (arrows, space, J/K). Power users use them, casual users never notice.
- The page count. People look for it, even if they don't need it.
What we changed
The toolbar moved from the top to a hover-revealed pill at the bottom-center. This freed 70px of vertical space — which on a 1080p screen is the difference between seeing a full page and seeing 92% of one. Mobile users get a permanent bottom action bar.
The page sidebar is gone by default. Replaced with a thumbnail strip that appears on hover near the page count. The strip is virtualized — a 400-page document renders the thumbnail strip with zero lag.
Zoom controls are gestural: pinch on mobile, scroll+meta on desktop. The explicit zoom buttons are still there but tucked into the toolbar pill, not staring at you.
What we threw out
- The print button. We'll add it back if anyone misses it. So far nobody has.
- The “rotate page” button. Auto-detected from EXIF and OCR.
- The bookmark sidebar. PDF bookmarks render inline as a slide-out from the page count.
- The find-in-page modal. Replaced with cmd+F that highlights inline.
- The legacy “view in fullscreen” button. The browser's F11 works fine.
The new things
A right-side “ask” panel for the AI assistant. A small “visitor presence” indicator at the top when the sender is also viewing. A “jump to last visit” button on second opens. Inline comments that drop down from a page edge rather than opening a modal.
The goal across all of these: the recipient feels like they're using a thoughtful piece of software, not a tool with a sales team. We measure feel, indirectly, via retention and forward rate. Both went up. We'll take it.
The honest part
A lot of what we did was take away. The hardest design conversations were about features we cut — every cut had someone internal defending it. The viewer is better for the cuts. Restraint is the design discipline that scales the worst because nobody gets credit for the button that didn't ship. We're trying to.