Some good reasons for Over-Scrolling

Maximilian Böhm winlux at
Wed Feb 12 11:45:48 PST 2014

I have recently upgraded to Firefox 27 for Android to find with horror
that the Bounce Back/Rubber Band scrolling effect had been removed
I've been an iOS user for years and value the high amount of detail
magic that Apple has put into its iOS UI concept. One glorious detail
is over-scrolling. Whenever I have picked up an Android device it
bugged me that it had no rubber band, nor bounce back. Then I have
tested a new build of Firefox for Android and was overly happy that
you guys put this feature into it. It was one of my main reasons to
finally wage the switch to Android on my main mobile device.
Now you have removed it and I wonder why. I know that Apple has
patented its invention but there was a case [2] and the patent was
ruled invalid. This was after Google had already avoided the patent by
using blue glow in Android 3+. Blue glow became the standard for most
Android devices and I suspect that you received letters from irritated
Android-only users who don't grasp why over-scrolling is a good thing
and only see that it seems an alien UI metaphor in an Android app. But
platform consistency for its own sake isn't worth it IMHO. I want to
give you some serious reasons for keeping this metaphor:

* Without over-scrolling Firefox feels less organic, technical, not
like an object that you manipulate. It feels like a PC program and the
loss destroys the psycho-haptic immersion.
* Without over-scrolling you can't easily see so fast when you are at
the left/right/top/bottom. Is this the page boundary or is the app
* Missing overview over LONG websites via zooming out!
* Zooming out: It suddenly stops, you have a moment of irritation,
then you feel cramped because there is no further zooming.
* If the page is zoomed out at max already (and you don't know the
zooming level) a pinch gesture scrolls the page. It doesn't feel

* With over-scrolling: The elastic frame tells you immediately when
you reach the max and you don't feel cramped, nor does the program
feel stuttery.

The over-scrolling effect is skeuomorphism at its best: It is
borrowing a metaphor from real life that the human brain intuitively
recognizes. It is not bad skeuomorphism, it isn't a wooden table
texture. It is the right amount of skeuomorphism so that the brain
gets a help without fooling it with a faked real life object.

I encourage you to not just follow Google's decision - Google had to
avoid a valid patent at its time that isn't valid anymore. Google has
built its Holo design around the blue glow metaphor but you can stand
out. Users won't understand the difference by intuition but they will
*feel* the better concept behind. You can have a *better* FEELING for
the user than Chrome. Maybe you should gather user opinions in tests
(no, not with a survey on Android Central fanboy base. ;) ). You can
stand on Apple's strong research in usability. In doubt, you could
make an option(R) in settings for sophisticated users with the demand
for a fluid UI experience (oh, please!). You can emancipate yourself
from Google's disputable platform decisions and build the very best
experience for your actual users.
You are the makers of one of the fewest browsers on Android that can
do this stunt and ignore the blue glow patent avoidance because you
have your own rendering engine. Be proud of that and use its unique

Thank you for your reading time.

[1] "Browser
should show highlight instead of over-scrolling when panning beyond
page boundaries"

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