“They had the simplest task in the world.”
This is a really nice set of transitions when pinching in and out in Photos in iOS 26.
This is trickier than it seems, because it’s not just a linear zoom (like it would be in Maps or Sketch, for example). It’s a zoom and reflow – from 3 items to 1 item per column – which makes things a lot more complicated.
Here are a few nice details about this transition:
- It reacts to your fingers rather than being a rigid transition with a fixed duration.
- It always prioritizes the photo you’re pinching in and out, assuming that’s where you look.
- It smoothly transitions the aspect ratio (from always square when the items are smaller, to native when items are bigger).
- It crossfades the other photos. Cross-fade is the “cheap” answer for transitions, but here it feels appropriate, as it happens in the periphery – actually trying to move the other items linearly between their respective positions would feel unpleasant and distracting.
- In contrast to the other transitions, these crossfades are not fully tied to fingers, meaning you cannot stop in the middle of a crossfade.
Nikita Prokopov on his blog published other examples of problematic transitions, and it seems most of them are struggle in the same way, as transitions that cannot simply be linear. The above transition in iOS shows it’s possible to do it well if you care.
And it’s not just about smoothness or nice feelings. Prokopov:
[…] Desynchronization can lead to a lot of confusion. For example, in Photos, when switching between Crop and Adjust mode, picture snaps into place immediately but the crop border is animated.
This creates a false feeling that something subtly changes when you switch between modes. And you know what? I don’t want my UI to give me false feelings. I want it to be a precise instrument, not an animated toy.
The above iOS transition feels very precise to me.