
Dual-touch smartphone design concept - assaflavie
http://blog.assaflavie.com/touch?
======
joshmlewis
Ok, try picking up your phone and trying out the movement on the back of the
phone that this would require. It doesn't work. If the majority of the phone
is touch sensitive how are you supposed to hold it? It makes for really
awkward movement of your hand and let's say you figured out how to get the
scrolling down, you still have A HUGE issue of UI. The iOS experience nor its
apps were made for any kind of cursor or mouse interface.

If you need to reach across the screen without taking up screen real estate,
use your other hand. Or use a stylus. Problem solved.

Edit: Also not to mention that for the most part iOS does a pretty good job of
letting me be pretty accurate with my bulky fingers. It's not perfect, but
it's certainly not terrible.

~~~
hughes
My hand is in contact with the touchpad on my laptop almost constantly, but
this rarely causes any unintended interaction.

~~~
gatehouse
I had to turn off touch to click on my MacBook Air because I often brush the
pad with the heel of my hand while typing, causing the OS to refocus on
wherever the cursor happened to be.

~~~
mikepurvis
Isn't it off by default?

I like the physical click way better, in any case.

------
nutjob123
Sony has already released a gaming console with this feature, the PS Vita.
[http://www.modojo.com/features/playstation_vitas_rear_touch_...](http://www.modojo.com/features/playstation_vitas_rear_touch_pad_putting_it_to_great_use)

~~~
djhworld
It's of limited use though.

The only game as far as I'm aware that properly makes use of it is Tearaway,
but even then it only appears in a few places and was kind of awkward to
control properly.

~~~
georgemcbay
The Little Big Planet games use it too, in a more limited manner.

It is in fact awkward to use, IMO, and not just because of the software or
Sony's implementation.

There are at least two big problems with it:

One is that it is really difficult to do Wacom-pen style hovering of a
"cursor" on a capacitive surface with finger input in a way that works well
universally for everyone without a lengthy and awkward calibration. And
because of the non-direct method of interaction using your fingers on the back
gives you, you really need some sort of non-action hovering indicator for this
setup to work well.

The other is this: Put your hands in the positions shown in the original
article. Now try moving your your index and middle fingers around as if
touching the back surface of a device and try not to move your thumbs (and
wrists) all over the place involuntarily. For most people this is difficult.
When you are tightly gripping a device this becomes less of a problem but
still contributes to the whole thing feeling very uncomfortable and unstable.

I'm nearly positive that various companies like Apple must have tested
something like this out (either before/after the PS Vita) for a phone and just
found it to be a poor solution when implemented in a real-world prototype.

------
yig
"LucidTouch: A See-Through Mobile Device" by Daniel Wigdor, Clifton Forlines,
Patrick Baudisch, John Barnwell, Chia Shen. Published at UIST 2007.

paper:
[http://www.cliftonforlines.com/papers/2007_wigdor_lucidtouch...](http://www.cliftonforlines.com/papers/2007_wigdor_lucidtouch.pdf)

video:
[https://www.youtube.com/watch?v=qbMQ7urAvuc](https://www.youtube.com/watch?v=qbMQ7urAvuc)

~~~
raphman
And more on this topic: "Back-of-device Interaction allows creating very small
touch devices" by Patrick Baudisch, Gerry Chu (CHI 2009):

[http://patrickbaudisch.com/projects/nanotouch/](http://patrickbaudisch.com/projects/nanotouch/)

------
pmjordan
As I understand it, the PlayStation Vita has a rear touchpad. I've never used
one, does anyone who has care to comment on how well it works?

~~~
jerryr
I have a Vita, but the only game I've played that uses it is Tearaway. This
game doesn't use it for precision navigation or selection, so it's hard to say
how well a rear touchpad would work for that. Tearaway employs the rear
touchpad for tapping to jump and pushing objects around. For that, it's
surprisingly effective and adds a fun--if gimmicky--element to the gameplay.
The Vita is quite a bit larger than most smartphones, and I could see problems
with differing hand sizes requiring people to adjust their grips to use its
entire surface--probably not as much of a problem on a phone. The Vita is
played two-handed. I think a one-handed grip while using the rear touchpad on
a smartphone would be more difficult as your finger's range of motion is
limited. The OP article seems to anticipate this by focusing on small gestures
rather than ones that would take your finger across a large surface.

On a tangent [Tearaway Spoiler Alert]...when beginning the game, Tearaway asks
you to select your skin tone from a few presets. Knowing nothing about the
game at that point, I thought that was really strange. I recall thinking, "I
don't really care whether my character has my skin tone...and it's really odd
that they'd presume that I would." But it turns out, that's not what the skin
tone selection was for. In Tearaway, you use the rear touchpad to punch your
fingers through the paper backdrops of the game to manipulate things. The
first time I did this and they showed "my" fingers in the game, I was startled
for a split second and then laughed out loud. Screenshot of the effect:
[http://media.officialplaystationmagazine.co.uk/files/2013/11...](http://media.officialplaystationmagazine.co.uk/files/2013/11/20131101-tearaway-
review-20.png)

It's more magical live as your virtual in-game fingers track the position and
angle (angle presumably by extrapolating based upon the current finger
position and average hand size/grip) of your actual fingers surprisingly well.

------
ortusdux
The Notion Ink tablet originally had this back in 2010. It was disabled and
eventually removed entirely. There were rumors that it was squashed by an
apple patient, but I cannot find anything more substantial.

The whole NI tablet debacle made me quite jaded towards miracle tech. I'm
lucky it predated kickstarter, because I would have most likely backed it up
to 50% over retail. It's probably why I don't own a 1st gen pebble.

Here is a good overview of the concept's rise and fall:
[http://www.engadget.com/tag/NotionInk/](http://www.engadget.com/tag/NotionInk/)

~~~
gcb0
it is one of those things that seem perfect on paper. and may even be good for
the power user. but everyone knows that power user and consumer hardware are
not a good match.

you are right about the apple patent. Apple bought fingerWorks in 2005 and
killed ALL the loved product lines (of note, one keyboard that was in its
entire area, a touchpad). apple sit on top of the company's IP assets and used
it for nothing but suing people. ...and people still wonder why i avoid any
apple product..

anyway, eventually the touch screen tech made it to the iphones. or so they
say. but if you compare the fingerworks tech on the few shipped keyboards and
the iphone resistive touchscreen, they have little in common. apple was just
trolling everyone with the patents and killing innovation all around.

but since fingerworks was dead since 2005 thanks to apple, several other
companies with employees that probably never even heard of finger works
developed this idea... nokia as you mention. sony with psp. motorola with the
backflip (which being one of the first AT&T exclusive android phones suffered
of having the worst crap of custom android ROM that ever saw the light of
day). And more recently the Oppo N1 already have the very same implementation
idea mentioned in the article, and is in production. but you don't see anyone
rushing to the stores.

------
gfodor
as others have mentioned it's not a new idea. i think the reason you don't see
it in Apple products at least is because it is a step backwards in terms of
metaphor. the iPhone's core metaphor is direct manipulation. this requires
that your brain visually connects the motion of your finger with the objects
on screen. if you manipulated things via the back touchpad, this illusion
would be broken and it would feel more like interfacing with a traditional
computer and less like direct manipulation.

~~~
arrel
That sounds like the reason Apple refused to use a hardware button to trigger
the camera shutter, but thankfully they caved on that one and I can take a
photo without having to guess where I'm tapping the screen.

I'd rather see companies trying out ideas that might work instead of just
sticking to their metaphorical guns.

~~~
gfodor
Well every design change is a trade off. Breaking metaphors, all other things
being equal, is bad. The fact that the author here identifies an on screen
cursor as a use case probably is enough to strike fear in any apple designer
that this would lead to a regression in ux.

------
dnautics
How about instead of a 1:1 touchpad on the back, which could have problems,
Put a trackpad on the back of the phone, but have it just be a small square.
So it wouldn't be a "full-fledged" touchscreen, but a small touch sensistive
section. You could also have a discrete capacitance detecting sliver on the
side of the phone so that it's only active if you're physically holding the
phone. Clicks would happen using a button.

~~~
ATLobotomy
Why does it have to be on the back? Some old Android phones had a trackball
(or an optical sensor like on a mouse) to be used as a sort of cursor. The
Palm Pre had a small touch sensitive area below the screen that could be used
for OS specific gestures (much better integrated than what Android used the
trackball for IMHO).

All of these ideas are pointing to the issues in the use of a touchscreen as
input (imprecise, blocks screen during use, etc), yet for some reason they
keep getting used (and even taking over regular buttons).

I hope that this decision is being tested by the companies HCI departments,
but I worry that marketing is deciding that changing the input would be too
much of a risk (or cause fragmentation).

------
henryli
Apple, Google, and others have patented concepts around this. No clue whether
they're working on them...

[http://www.slashgear.com/google-patents-rear-touch-
controls-...](http://www.slashgear.com/google-patents-rear-touch-
controls-6-years-after-apple-09273179/)

[http://appft1.uspto.gov/netacgi/nph-
Parser?Sect1=PTO1&Sect2=...](http://appft1.uspto.gov/netacgi/nph-
Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=%2Fnetahtml%2FPTO%2Fsrchnum.html&r=1&f=G&l=50&s1=%2220070103454%22.PGNR.&OS=DN/20070103454&RS=DN/20070103454)

------
tgb
I suspect that Apple, Samsung, etc. have thought of this, so why aren't they
doing it? (After all, the PS Vita has had a back touchpad for a while.) The
first thing that comes to mind is that people hold their phones with the back.
Accidental clicks would be very difficult to avoid. In contrast, the PS Vita
is larger, held with both hands and has non-touchpad areas of the back where
you can grip it, as I understand.

I'd still like to see someone try it.

~~~
bobbles
People also use their phone with a case

------
kevingadd
Sony put this into the Playstation Vita and it's awful. Few games use it, and
it's clumsy in the games that do. It's possible that a company like Apple
could make it good somehow, through sheer will and hardware/software
expertise, but I suspect it's just not a good idea in practice even if it's
good on paper.

Based on my limited experience, some potential issues:

Not having the user's fingers obscuring the view of the screen may in fact
increase the perceived latency, since they're focused on the screen and don't
have the motion of their fingers to distract them.

The latency issue would be twice as bad if you want to render a 'ghost' of
your hands on the screen as described in this design concept.

Interacting with onscreen elements is _more_ difficult when using your hands
on the rear of a device, even with a 1-1 mapping. I don't really know why this
is, but even with a cursor onscreen, I have found it to be true.

Accidental interaction is 5 times worse with a rear touch panel. Apps on the
Vita that use it extensively are a huge pain in terms of accidental swipes and
touches, especially if you try to lay the device down on a surface for a
moment, or set it on your knee to use the front touch panel.

The core problem with virtual buttons/joysticks/gamepads is that you have no
physical feedback about where your fingers are, and as a result you lose your
'centering' and your inputs end up being misinterpreted or not landing. Moving
your fingers to the rear of the device makes this worse, because you can no
longer look at your fingers to figure out where they are.

------
ekr
I don't know anything about how well this works or how well it was made:

DOOGEE DG800 : sub $120 smartphone with dual touch :
[http://www.pandawill.com/doogee-valencia-dg800-smartphone-
cr...](http://www.pandawill.com/doogee-valencia-dg800-smartphone-creative-
back-touch-android-44-mtk6582-45-inch-otg-p89140.html)

------
ereckers
The first thing that came to mind was the Nokia Gem concept from around 2011:

[http://conversations.nokia.com/2011/11/10/nokia-gem-what-
sor...](http://conversations.nokia.com/2011/11/10/nokia-gem-what-sort-of-
phone-do-you-want-today/)

The whole thing was a touch screen.

Here's an Engadget article on the Nokia concept with a fair amount of
comments:

[http://www.engadget.com/2011/11/11/nokia-gem-concept-
dazzles...](http://www.engadget.com/2011/11/11/nokia-gem-concept-dazzles-with-
excessive-customization-options/)

------
jimfleming
Sensus ([http://sensusxp.com/](http://sensusxp.com/)) is working on something
similar as an external case for the iPhone. Dislaimer: I have a dev kit.

------
r0h1n
> "The biggest problems is that your fingers are not transparent. They obscure
> the screen."

I've _never_ realized this was even a problem, much less the biggest one.

~~~
jader201
Yeah, my biggest issue with touch screens by far is the lack of precision.
This point seems a bit silly as your fingers typically move fast enough to
allow your memory to recall the image.

 _Maybe_ in games this is more of an issue, especially where you need to leave
your fingers in the same position and the design of the game does a poor job
of taking this into account. But those are mostly edge cases.

~~~
andrewflnr
The problem with precision _is_ one of visibility. In my experience, the
problem us that I can't see the exact spot where the device thinks my finger
is because my finger is on top of it. This is at least the case with text
selection.

------
Gregordinary
The Motorola Charm had a trackpad on the back of the phone. I know it could be
used for scrolling, not sure if it worked in the same capacity as the dual-
touch design concept. [http://www.oneprice.in/wp-
content/uploads/2011/10/Motorola-C...](http://www.oneprice.in/wp-
content/uploads/2011/10/Motorola-Charm-MB502-1-Optimized.jpg)

------
rcchen
The Motorola Backflip
([http://www.gsmarena.com/motorola_backflip-3079.php](http://www.gsmarena.com/motorola_backflip-3079.php))
actually had a touch pad in the back that could be used in the same way
trackballs were used on Blackberries. It was pretty awful to use, though that
might have been because it ran Android 1.6

------
apple314159
Makes more sense to use the front camera as an eye tracking device. Then you
get a screen without obstruction. Maybe Apple is already on it:

[http://www.patentlyapple.com/patently-apple/2013/10/apple-
fi...](http://www.patentlyapple.com/patently-apple/2013/10/apple-files-eye-
tracking-system-with-advanced-gaze-controls.html)

------
acd
I think the future of smartphones are foldable either in the middle like a
foldable sheet of paper or expandable flexible oled displays formed like
Chinese hand fans or origami.

Further more the cell phone of the future will be able to borrow any big
screen in its vicinity. Something like NFC from the large display/computer
monitor and built in AppleTV, Google Chrome MiraCast functionality. You will
also be able to borrow local keyboards for better input, but without the
bluetooth hassles of setting it up. So the cafe, workplaces of the future will
have wireless chargers and screens that you can borrow for your mobile device.

So you will carry your device around but borrow larger displays and keyboards.
The device will be powerful enough todo your everyday computing. No need to
drag a big laptop around if you do not want to.

These devices will also be user serviceable like Google/Motorola Project Ara.
It is simply not good for the environment to throw away a whole phone just
because the display, battery is bad or because you want to upgrade the radio
components. So in the future devices will be made to be recyclable, this trend
will be driven by the scarcity of rare earth metals. It will simply not be
good enough to buy and throw devices and not think about the recycling of rare
metals and the environment.

The future is bright.

------
enscr
Now that @assaflavie has written about it, does it constitute as 'prior art'
and nobody can patent it?

~~~
josho
Exactly that. You cannot invent (patent) something that has already been
invented. Now you could go ahead and invent (patent) something that builds on
his ideas, as long as those ideas are a novel addition (not an obvious next
step).

~~~
lnanek2
Isn't it first to file nowadays, not first to invent? Not that there aren't
shipping phones and other devices with this already anyway.

------
perlpimp
... "The samples will be missing lots of implicit information such as how to
install the necessary libraries and how to deal with missing dependencies and
version conflicts." ..

Even people who grasp code pretty well loading up some code(stable library)
needed by tutorial might get tripped up by a wrong advice such as library that
was fixed for some security vulnerability that broke a number of thing that
current examples need to work and failing code just misbehaves in a number of
ways, one remarkable - blaming general implementation of examples that they
are trying breaking security standards and not give any alternative to do
otherwise. that is unless you find a reference somewhere on some obscure blog
that says that you have to load specific version pre-alpha/HEAD^3 because HEAD
is broken so many subtle ways that it will cause you even more pain. This
happened not once and not only to me I bet. I know I could've patched my code
but with the deadline and fact that I don't know much about cryptography that
would not be a sane option.

~~~
sparkman55
Perhaps you meant to post this here?

[https://news.ycombinator.com/item?id=7760790](https://news.ycombinator.com/item?id=7760790)

------
jotm
That's a good idea and all, but you know what would be better than two touch
panels? A button to turn them off!

With screens bigger than your hands and accidental touch detection being as
bad as ever, a simple button to turn off the digitizer would make a lot of
people happy...

------
avivo
This seems particularly useful for very small touch screens, assuming you can
comfortably hold the device without miss-clicks.

Perhaps a smart watch could even have its screen on one side of your wrist,
and a "touchpad" on the other.

------
nnutter
The Notion Ink Adam tablet, from a year or two ago was going to have this
feature.

------
freeslugs
There was something like this at the CES (consumer electronics show). They had
it with an iPad. Not sure if this is the most practical idea.

------
Fuzzwah
The oppo n1 has a small rear touch pad.

[http://en.oppo.com/products/n1/](http://en.oppo.com/products/n1/)

------
ookblah
what about everyone who has a custom case of some sort on their phone? pretty
much negates that...

~~~
tyrust
Then don't put a cover on your phone? What a strange criticism: "If I make
this thing not work it won't work".

------
charlie_vill
This is the sort of content I intend to find on Hacker News. This is why I am
here.

------
design
The best thing touch screens have going for them, though, is direct
interaction.

------
cjbenedikt
It's impossible - until it's done. Patent it! ;-)

------
finalight
for scrolling maybe

for gaming, most likely uncomfortable users are used to using thumbs to play
rather than using their index fingers

i rather be waiting for those kind of panel-less screen

------
karangoeluw
Would be pretty useless if the phone has a case.

------
shahocean
Apple was working on it at some point! so as Google!

------
gdi2290
Sony called, they want their PS Vita back

