A mobile design anecdote on perceived latency and touch feedback

Fast can sometimes feel slow.

I was on a bus today when I noticed the passenger in front of me using her iPhone. I observed two behaviors that support the mobile design best practices I and others have been talking about on Android Design in Action and elsewhere on the interwebs.

First, the bus passenger was using some app with a touchable photo banner near the top of the screen and some text below. She touched the photo, but nothing happened. The app didn’t visually respond, even for a moment, and the content didn’t load. So within a second or two she touched again, and this time the photo did open.

Onto the second observation. She left the first app and opened up Groupon. A splash screen popped up, but after a second or two of waiting, she just pressed the home button to browse through other apps.

These two observations support the notion that perceived latency and visual touch feedback are important and intertwined. The first time the bus passenger touched the photo, the touch screen may not have registered it, or treated it as a swipe rather than a press. Dimming or otherwise highlighting touch regions throughout the app on press would’ve immediately conveyed success and contributed to stability and comfort in the UX. Additionally, if content loading time was nontrivial (and prefetching wasn’t possible), a subtle indicator could’ve communicated that the touch itself was successful.

And as for the splash screen, well she didn’t open the app to stare at the logo, however pretty it may be. Every millisecond you’re not showing content is a millisecond that the user has to wait for something. We wait enough in our lives: we wait for the train, we wait on line at the grocery store, and we wait—often impatiently—for our significant others while they’re busy getting ready for a night out. We shouldn’t exacerbate the problem when the platforms we’re building for give us the necessary tools to avoid it.


One final note—I didn’t ask the passenger what she thought of the apps she’d just tried to use, but I did ask a non-techie friend a few weeks ago what he thought about some of the apps on his phone. He, like many others would, thought some of his least favorite apps were simply “slow.”