MOTO gives straight advice on smartphone touchscreen quality (video)
By Thomas Ricker 
posted January 9th 2010 3:04PM
posted January 9th 2010 3:04PM
Update: Test under medium pressure after the break.
posted January 9th 2010 3:04PM
HTC Google Nexus One
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Great so you can draw straight lines on the Iphone..but it still drops calls like crazy.
@(Unverified)
engadget is so pathetic that they cheat on results. If you read the full test iphone is the worst one, along with droid.
For shits and giggles I wish they would have included the HD2 and Palm Pre.
@stockjones Agreed.
@stockjones I too would like to see how palm did.
BTW....Droid owners are trying this experiment and getting quite different results (as in straight lines)...just like they got different results on the browser speed tests (and documented it on video on You Tube)...something is fishy for sure. Check out the Droid forum for more...
@(Unverified)
it's engadget that is TERRIBLY biased.
I think this article does indeed prove Engadgets Apple bias. Not because of the test but the picture they selected.
They could have easily used the image underneath as the main article picture which shows the Nexus One having straight curves along side the iPhone however they show one that doesn't...
It's the simple and little things that Engadget do that proves this.
@Psyg It does look quite jagged now that you mention it, kinda like performing this test on the other phones while driving, and the iPhone at a coffee house.
What I wonder is how do slow straight lines equal inaccuracies in quick-tapping on the on screen keyboards. Like he said, the quicker the stroke and fewer points of interest, the straighter the line. I don't know anyone who types slow enough to really see a huge mis-key on any of the phones in this test. From what I've experienced, I mis-type as often on my old iPhone 3G as I do the Hero and Droid (waiting on taxes to get my Nexus One). Also, where is the Pre/Pixi in this test?
Engadget with more lies and iphone rocks BS. G T F O H
Would have been nice to see the Palm Pre tested.
On the other topic going on in here, I feel Engadget is pretty fair overall. I don't hate any phone/platform, hell I have never even used an iPhone or Android. I know the iPhone just isn't for me because I don't like the locked in ecosystem (I am a Linux guy after all). Still I hear positives and negatives for all phones on this site and in their podcast. Like I said, pretty fair IMO.
@Cringer *GASP* What?! Oh my, someone who didn't say Engadget was biased.
They give credit where credit is due, don't be mad at them because Apple is doing great things.
And they didn't est this with multiple drawing apps?
Come on guys, the last minute edit won't cut it. Pics are popping up all over the mobile phone forums of people repeating the test on their Droids and Nexus Ones and getting the EXACT same results as the iPhone pics above. The review was bogus.
Iphone takes this one. That said, devices that only have a touchscreen with no dedicated keyboard NEED to have top class touch response. I'd be willing to give a bit more slack to devices costing the same to make but with a dedicated keyboard...but maybe not as much slack as the motorola droid shows...
I blame gorilla glass....
@DaSongMan Edit: saw the forum posts, bogus indeed..
The real question here is who actually believes anything posted by Endgadget. They lost all credibility since the very first time posting about Android. Lol, obvious fanboys are obvious. How deluded can you be, N1 is the better phone. iSold my iPhone and got the nexus 1. Stop being totally deluded Endgadget.
Look, this test is accurate. I just did the same thing on my iPhone (3GS), and got very similar results to the guy in the video. I used a drawing app that I wrote, and I can tell you, IT DOES NOT USE SMOOTHING! I also did the test much slower than the video.
http://www.flickr.com/photos/35101661@N02/4262781787/
Hi Everyone,
Morgan here from MOTO. Yep, I'm the guy in the video. It's amazing to see such an active discussion around this simple set of images. Thanks for blowing this up!
An especially big thanks to those of you who tried it and posted results here!
A lot of folks have raised a lot of interesting points here which merit further discussion. I want to address a few key things:
First of all, we don't intend this to be a rating of the phones as products. We are looking at touchscreen performance here. I could lecture for hours about the nerdly specifics, but the truth is, we're just trying to share a DIY approach which consumers can use to get a quick understanding of the performance of devices.
It's not meant to be journal-quality scientific authorship.
Second, just for the record, I am not an Apple Fanboy. I am greatful to Apple for marketing this stuff so heavily, because it drives competition focused on integrated user experience rather than raw features. As an alum of the glory days of IDEO, I'm into that kind of thing. I use Ubuntu at home, XP at work, have an iPhone, many Zunes, many iPods, Sansas, iRivers, HTC phones, Samsung phones, MIDs, tablets, etc. You name it, I've used it, torn it apart, criticized it in frustration, and done my best to understand WHY the designers and engineers who built it made the decisions they did.
I have a Nexus One at the moment, and I'm stoked about it.
I would like nothing more than to see really high quality, ultra-linear touch solutions from every vendor. In my day-to-day work as a product development consultant, that's good for everyone.
Here are some good points many of you have made, with my comments to help clarify:
1) "You drew crappy lines!!1!"
Yes, yes I did. If you do it by hand, it doesn't look pretty. But I promise you, I don't have a tremor which leads to a perfect 10mm periodicity in the waviness of the motion of my fingers.
The clearly-periodic waviness you see is from the sensors, not my finger.
Maybe next time we'll show you how we do it for *real*, with the robot sitting behind me in the video, but the idea in this post was to show something you can do on the floor at Best Buy if you're so inclined.
Try it yourself!
2) "You drew faster on the iPhone!"
In the video, I did. Sorry. But in the images shown in the photos, I didn't, I swear. I drew so damn slowly in those it was aggravating.
Even if I drew 30% faster in the video, the iPhone sensor samples at a rate about 30% higher than the other devices tested, so it's still not a horrible error. The linearity demonstration is legit.
Try it yourself!
3) "Software can fix that bad touch data!"
Not necessarily. Depends on why it's bad.
If you have some grounding in remote sensing or signal processing, you know that there are certain limits to how much information you have to work with from a transducer of any sort.
Good algorithms can compensate for weird non-linearities (like, say, wavy lines!) in some situations, but you CANNOT create signal where there is none.
One reason Apple's touch sensor is so sensitive to light touch is that they use 12V drive versus 3-5V for most solutions on the market right now. It costs more power, but you end up with considerably higher voltages to sense, which means higher fundamental SNR coming out of the sensor. This is a *huge* advantage, and it's something that any touch vendor COULD do if they wanted to.
4) "Medium touch on Android works as well as light touch on iPhone" (@recharged95)
Yes. This is true. However, really light touch is useful for making flicking around menus and maps feel more fluid -- if you have to push against the screen, you have to deal with more friction.
You can certainly design your UI around the flaws in your sensing apparatus, like, say, bad edge performance, or bad linearity.
You increase the target sizes, put stuff in the center of the screen, etc.
But you're paying for that by sacrificing creative freedom.
Every touchscreen should try to be perfectly linear everywhere, so people can build whatever UI they want.
The experience of using a smartphone is the fusion of a massive number of people's design and engineering expertise -- typically a team of 50-200 people or more, when you start counting the design teams at the big ODMs like FoxConn, Quanta, Flextronics, etc.
These products are supposed to be integrated experiences that balance every aspect, from the lightness of touch you can use, to the smoothness of onscreen animation, to bells and whistles like Google Maps and compasses and gyros and accelerometers, too.
Don't sell yourself short! Demand the best performance from the gadgets you buy in every aspect!
5) "Keyboard performance is hurt more by edge issues than overall linearity issues" (@recharged95)
Not enough information here. Honestly, I've sat in the user test labs and run these tests. I've seen the error rates which real people have on different touch keyboards, and if the data were not proprietary to my clients, I could share examples demonstrating that overall linearity problems with light touch CAN and DO significantly impact typing performance.
A few mm of positional error is a big deal for your key error rate when you're typing 1000's of characters.
6) "The lines were fat on the Droid in the video"
Yes they were. Sorry about that. For whatever reason, I couldn't get the Droid to download the simple drawing app I was using ("DrawNoteK") until I got to CES and we'd already shot the video with another app ("Draw! Free").
On the iPhone we used SimpleDraw.
The hand-drawing I did on the photos was much more consistent than in the video.
I just got "SimpleDraw" on the Nexus One, which I like even better, as it has thinner lines. We'll probably use that in the future, as it supports multitouch input (at the SW level).
I hope that's the same author as the iPhone version!
7) "You used different software!"
Yeah, we didn't have time to fix that in the video. But all the *photos* were done with DrawNoteK on the android devices.
Honestly, I have a pretty refined eye for this stuff, as I've written all kinds of SW for data visualization, and I don't think DrawNoteK or SimpleDraw is doing any major smoothing.
CERTAINLY not to an extent which would hide the waviness we observed.
8) "You excluded the Pre you insensitive clod!"
I wanted to include it -- there's one by my desk, and I know the team that designed it. But I couldn't for the life of me find the login credentials for that particular device.
I'll probably test it next week just for kicks. I might post the result on our labs.moto.com website.
9) "My Pre/Hero/Whatever performed differently and I can prove it!"
Of COURSE it did. You used your finger, your hand, your muscles, your electromagnetic environment, and your device.
The range of finger contact patch size for normal people ranges from about 5mm to about 15mm diameter for those with really big finger pads. It's wildly organic. Some people drag lightly, some people stab at buttons, some people scrub firmly across the surface. The amount of oil on your fingers varies widely, too -- this means different lubrication properties while sliding.
That's why this is a DIY test!
You really may get great results with a device that I get mediocre ones on!
Try it yourself!
10) "Analog resistive touch screens kick capacitive screen's ass for linearity"
Hell yes they sure do. And they work great with stylus. The only problems are:
* they don't do multifinger (do you really care? maybe not...)
* they require force to actuate, so they don't work as well for light touch flicking-type interfaces
* they have worse optical properties than capacitive screens, because they generally include air gaps
Stantum, TouchCo and others have some interesting stuff to show on the multitouch resistive front, but they don't fix the no-pressure-required problem. Still, I'm excited to see scanned digital and hybrid systems come to market. It's gonna be super cool, and will offer some cool differences versus capacitive, especially in the glove/stylus space.
11) "No way! You're just trying to make the iPhone look better!"
Really, honestly, no. I'm a Freedom and competition guy.
I have played with touch dev kits from *every* other manufacturer, including plenty of stuff that's not on the market yet, and these wavy artifacts are always a challenge. Apple has been spending a lot of money paying a lot of smart people working on this for a long time.
There's good news, though: most of the silicon driving these touchscreens is a generation out of date already. The HTC phones only do "1.5 touch" right now -- fine for pan/zoom, but not for good rotation or "Ocarina"-style true multifinger input.
Just about everyone will have stuff shipping with true multitouch and much more refined algorithms and sensor designs Real Soon Now, so it's gonna get better fast.
It's going to be a great year.
Thanks for listening, and for keeping the pressure on the manufacturers in the blogosphere!
Sites like Engadget light a fire under the OEMs to build better HW -- don't worry about iPhone-centric journalism -- that just scares the big boys into trying harder. A rising tide, and all that.
cheers
morgan
@motomorgan
also considering resolutions since apples resolution is 320x480 and others are 800x480 or 852x480 would that also be a factor with the signal to noise ratio and skewed dpi mapping?
@motomorgan
Thanks for taking the time to come in here, read the comments, and post all that. I think I can speak for most Engadget regulars when I say that we like feedback and furthered discussion! :)
@xconan
With regard to LCD/OLED screen resolution:
It's not an SNR question per se, but yes, it can matter to the results.
The touch panel is a separate component and not related to the screen. Capacitive touch panels out there right now have a sensor matrix which is about ~12 x ~18 (depends on aspect ratio, of course), sometimes less. That means that all of the fine positioning happens through interpolation of the data on adjacent sensors whose centerlines are 5mm-6mm apart. You can build much finer sensors, but the electronics aren't free, and everyone's trying to strike a balance.
The interpolated resolution of the touch sensor is actually quite fine -- generally much higher than 200dpi.
So if you have a really wide aspect screen, and you use a 12x12 touch sensor, yeah, you may strain the interpolation algorithm a bit more along the long axis.
This manifests as follows:
Two adjacent sensors are both sensing a finger.
One sees 60% signal, the other sees 40% signal.
So if everything's linear (it isn't really, but this logic still applies to 1st order), you figure the finger is at 60% of the distance towards the first sensor. Straightforward.
But what if the pitch is stretched really far, like 10mm between sensors on a super-wide aspect panel (say, 120x240mm)with a numerically square sensor array (say 12x12)? Then it might be possible that the signal from one sensor drops off completely as you move from one sensor to the next.
If you have 70% signal on one sensor, and nothing on any adjacent sensor (in the same axis), then you can only assume that the finger is directly in the center of that sensor.
Now, there are definitiely algorithmic subtleties which go considerably deeper, but this level of analysis describes most of the core problem -- any algorithm which tries to resolve the ambiguity of a finger over a single sensor trace MUST make a behavioral assumption about what the user is doing.
That can be useful if the behaviors of the user are very predictable, but in general they are not, so you have to tread carefully.
LCD *noise* is a very, very big influencer of overall SNR for the system. LCDs do a lot of switching right up against the touchpanel, and create all sorts of periodic and non-periodic RF noise.
Touch sensor companies spend a lot of time dealing with this.
OLEDs, being mostly current-driven, tend to be very quiet in this regard. It can be a significant advantage in terms of the time it takes to tune a new sensor/display combination, and generally yields higher SNR.
oh no now I'm gonna have to retrofit my iphone's screen in my droid !
Damn, what the hell? People are arguing over phones? That's childish. I have a right to say that. I'm a child.
One question: CAN'T WE ALL JUST GET ALONG????!??!?!?!!?!?!!!!?
Seriously, looking at phones and technology is fun, but we don't need to go to war about it. OK?
I'm not siding.
This is such a lame article. I tested this myself and I got WAY better lines. Who the hell was testing this on the nexus he musta been blind
The fact that your reviews are so biased makes me wonder; you probably get paid by Apple, dont ya !?
His test is misleading man. Totally tricky and mislead.
Try it yourself.
He is doing is slowly, giving viewer a feeling for accurate and straight. But actually its the other way around.
Only sensitive and accurate screen will create curvy when drawing at his slow speed. Try it yourself. He is such a liar.
What a bogus lab.
Using such a bogus non- scientific way (using bare finger to try to draw straight lines).
Creating mislead images on certain products by posting the actual product images.
Posting this bogus (non-scientific), misleading (comparing products with bogus results), high deviated (already updated test with major deviation) results in one of the world's top hits site.
This should have enough evidences to raise a libel case.
finger tracking or not, there's no multitouch on the Droid or Nexus One. So you can't put your thumb on the screen and run around while simultaneously using your other thumb to jump or shoot. A game like NOVA would be impossible on Android without multitouch.
but even worse, the internal memory of the phone is only a few hundred megabytes. And 192MB is taken up by the OS. Apps need to write themselves to the internal phone memory, not the external SD card. So the app has to be small which means the developer needs to cut corners. In order to maintain a very small footprint, developers can't use more graphics like they do on the iPhone. People have noted that Android apps don't look as polished and that's because they can't be.
don't worry though, it'll come in some future version of Android. All while Apple stands completely still and doesn't add another feature. Good thing we're all so patient with Google to take their time and get it right eventually.
if this dude is from motorola, why would they show something saying that the droid isn't as good as the iphone and droid eris
I didn't bother to troll the entire comments, but isn't this test more about Hardware than Software. It's always iPhone vs Android. To be entirely fair, it should now just be iPhone vs Nexus One if comparisons are to be made.
I'm not defending the iPhone, I am just saying that in this instance it seems to be that everyone is inentionally forgetting about the hardware.
Just tried this on my N97 and it gives better results. It loses shape at the edges, but that's because my finger hits the raised bezel, it still tracks correctly.
this is a complete load of trash. if anything, it shows that the droid's screen is MORE accurate because it doesn't take as much of an "average" of where your finger touches it. if it where possible to use a stylus on the droid, i would predict different results. they mention how this affects the keyboard. i can use the droid's virtual keyboard just as easily as i used my iphone's and there are more on screen keys on the droid. i don't really follow this site, but i do see that every time i visit it (from a link on some other forum) they pull every little nonsense "test" they can to debunk how great the droid is becoming. the camera sucks, and the slide out keyboard sucks (imho) but since the december update i have no regrets for ditching the iphone. i believe the iphone is the smoothest and most polished phone around, but all the things i hated about that damned thing are remedied with the android platform. my only concern is that google keeps popping out phones. do none of these other companies realize that the reason iphone works so well is because apple focuses on one iphone, not 1000 winmo or android phones? i thought the droid was going to be the flagship .... and it was .... for a month.,
I just did this on my N1, my results were much better than any of theirs, I had no skewing at all at the edges, light or medium touch. The comment that Moto made about the iPhone being the best in his test is asinine, based on what I get...ahhahhha, let the fanboys think their iPhones are the best, we all know better! Hell, in the video the Eris outperformed the iPhone overall
I have multi touch on my Android phones, both my G1's have it and my N1 has it, although it's in the browser only.
Do yourself and read the original test site:
http://labs.moto.com/diy-touchscreen-analysis/
It gives you the full story, that the iPhone is more accurate at the center but the Nexus One is more accurate around the edges.
the capacitive display of the iphone/touch plus the algorythm to analyze the motion of the finger is actually superb and unique the same goes actually for the accelerometer and so on.
i love my milestone (just like my ipod touch) but this is something you have to confess.