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If you do the math - the difference in Fitts ID between the two use cases is under 1%.
Ok, I did the math. I presume this 1% accounts for the resolution difference in the case of an iPhone (165ppi) vs. a 7.85" 1024x768 display (163ppi).

At the same distance, the iPhone actually has the higher ID.

<sips some more coffee>
 
:) Yes, D would scale with screen size. Just as people hold iPhones closer to their face than iPads - they would hold iPad Mini slightly closer than 9.7" iPad.

I was just watching the way my wife holds her Nook Color - she is holding it by one hand similar to a smartphone, probably about 10" away from her face.

I think it's great seeing this worked out.
I just take an empirical approach to things, and this seems to match what my experience has been here.

Almost makes this whole thread worthwhile...
 
... and I'm --still-- wondering what sanding my fingers down to 1/4 size has to do with any of this ...

A 7" tablet at 1024 x 768 compared to the then iPad's 1024 x 768 screen has 28% smaller pixels. Ergo... everything is scaled down by 1/4 size.
True, but 28% smaller is 72% size, NOT 1/4 (25%) size.
Even if you take the relative area into account (which is what Steve was doing) a 7" tablet would have about 50% area (he even stated this), this is STILL NOT 1/4.
A 7.85" tablet would be 81% size (only 19% smaller) and 65% area.
 
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True, but 28% smaller is 72% size, NOT 1/4 (25%) size.
Even if you take the relative area into account (which is what Steve was doing) a 7" tablet would have about 50% area (he even stated this), this is STILL NOT 1/4.
A 7.85" tablet would be 81% size (only 19% smaller) and 65% area.

Hey - I was trying to save that one for the kids ... :p
 
<Forgive me, I don't know how to insert an image within the text, so it appears at the bottom>

Fitts's Law

See the Fitts formula at the bottom, where:
T is the average time taken to complete the movement.

a represents the start/stop time of the device (intercept) and
b stands for the inherent speed of the device (slope).
These constants can be determined experimentally by fitting a straight line to measured data.

D is the distance from the starting point to the center of the target.
W is the width of the target measured along the axis of motion.

In the case, where we are simply reducing the size of the iPad by 19% to create an "iPad mini":
a and b remain constant;
D and W change proportionally, e.g. the target size is reduced by 19% and the distance to the target is also reduced by 19%.

Since the formula divides D by W the resultant T will not change.

There's a fatal flaw in your Fitts conclusion.

"Come on freudling, tell us!"
 
True, but 28% smaller is 72% size, NOT 1/4 (25%) size.
Even if you take the relative area into account (which is what Steve was doing) a 7" tablet would have about 50% area (he even stated this), this is STILL NOT 1/4.
A 7.85" tablet would be 81% size (only 19% smaller) and 65% area.

It is 1/4. The question was, "What did Jobs mean by sanding his fingers down 1/4 the size?". I showed how it was 1/4: it's implicit. Instead of using percentages, Jobs chose to just say 1/4 instead of 28%. I figured this out and this is fact. You wouldn't have even known this yourself unless I posted it. Now you're trying to make me look wrong by pointing out something that you think is a mistake (3% "error"), when in fact it's implicit in the calculations what the exact percentage values are and what Jobs was referring to.

Second, Jobs was not referring to a 7.85" tablet, he was referring to a 7" tablet, so calculations revolving around a 7.85" tablet in this context are completely irrelevant to the reference of sanding his fingers down 1/4 the size. He was referring to the diagonal size of the device.
 
The question was, "What did Jobs mean by sanding his fingers down 1/4 the size?"...
No it was not; the question was:
"... and I'm --still-- wondering what sanding my fingers down to 1/4 size has to do with any of this ..."'

Here is what Steve Jobs actually said:
“So that the user can sand down their fingers to around one-quarter of their present size”.

One quarter of their present size, NOT one quarter smaller.

He also said this right before:
"One naturally thinks that a seven-inch screen would offer 70 percent of the benefits of a 10-inch screen. Unfortunately, this is far from the truth. The screen measurements are diagonal, so that a seven-inch screen is only 45 percent as large as iPad’s 10-inch screen. You heard me right: just 45 percent as large."

If you do the math you can see he was actually referring to area.
 
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Can everyone just stop with this rumour? This has become one of the worst, overhyped Apple rumours I've ever seen.

First, the sources for these rumours are crap: often times it's some Chinese publication putting it out.

Second, the size will be a waste. Jobs is right, 7" tablets are tweeners. They generally suck for content. Smartphones are now so useful you really need a compelling reason to drop the handheld for a tablet. The iPad is just big enough to justify its existence in this respect. There's no way Apple is going to release it for this reason... In other words, it's a dead category. The only reason this stuff gets perpetuated is because of link whores and Apple's ever present disinformation machine.

"Keep em' guessing; distract them; thwart their offensive efforts; cause confusion..."

Samsung and Amazon have found success with 7" tablets. There are a lot of people out there who don't realy know the diffrence other than the 7" tablets are much cheaper than the ipad. Apple does not want to keep this market vacant, a $250 dollar ipad mini would put out Kindle's fire, and knock Samsung out of the Galaxy.

The leaks proved to be pretty acurate about the Ipad 2, not so much with Ipad 3. Iphone 4S name was in circulation when people thought a totally redesigned iphone 5 would arrive.

only time will tell.
 
You are generally correct - it's rather simple math. The relevant component of Fitts here is ID or "Index of Difficulty".

ID = log2 (D/W +1)
where D is the distance-to-target and W is the size of target.

In case of full-size iPad, D = 12" (roughly how far away I hold my iPad from my face), and W = 0.33".

In case of iPad Mini, D = 10" (slightly closer distance due to smaller size / weight / one-handed operation), and W = 0.27".
...
from the wiki:
W is the width of the target measured along the axis of motion.

If so, how could D be perpendicular to the surface?
Doesn't this statement imply that the axis of motion must be in the same plane as the target; e.g. moving a mouse or dragging some UI element?
I suppose the principle could be applied 3 dimensionally, but then it seems to require the target have some depth W that you were attempting to stop within.
 
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No it was not; the question was:
"... and I'm --still-- wondering what sanding my fingers down to 1/4 size has to do with any of this ..."'

Here is what Steve Jobs actually said:
“So that the user can sand down their fingers to around one-quarter of their present size”.

One quarter of their present size, NOT one quarter smaller.

He also said this right before:
"One naturally thinks that a seven-inch screen would offer 70 percent of the benefits of a 10-inch screen. Unfortunately, this is far from the truth. The screen measurements are diagonal, so that a seven-inch screen is only 45 percent as large as iPad’s 10-inch screen. You heard me right: just 45 percent as large."

If you do the math you can see he was actually referring to area.

I hadn't read this. When analyzing it this way, it makes the situation for tweeners even worse when viewing it from a decrease in surface area.

Regardless of what Jobs said or anyone else, the reality is that the device scales down diagonally by a percentage of 28% to get to the famed Mini size. So another way of saying it is that since the entire UI is scaling down at this rate, you'd have to sand 1/4 of your fingers down to account for the loss of the UI size.

Now, for Fitts... here's a clue: the diagonal scale... you realize that you have a device that has a substantially larger screen with the exact same button sizes as an iPhone with effectively the same logical DPI? This doesn't seem very good for usability since the device is held farther from the face and the screen is much larger... Let's see if you can figure out where you went wrong in your Fitts conclusion.

----------

Samsung and Amazon have found success with 7" tablets. There are a lot of people out there who don't realy know the diffrence other than the 7" tablets are much cheaper than the ipad. Apple does not want to keep this market vacant, a $250 dollar ipad mini would put out Kindle's fire, and knock Samsung out of the Galaxy.

The leaks proved to be pretty acurate about the Ipad 2, not so much with Ipad 3. Iphone 4S name was in circulation when people thought a totally redesigned iphone 5 would arrive.

only time will tell.

No, the Amazon Kindle Fire is not successful. Not in the least. It sells almost as bad as the RIM PlayBook. It had a 4 week initial push but that's dead long ago. The device is a complete failure in the market.

http://www.geekosystem.com/kindle-fire-2012/

----------

from the wiki:
W is the width of the target measured along the axis of motion.

If so, how could D be perpendicular to the surface?
Doesn't this statement imply that the axis of motion must be in the same plane as the target; e.g. moving a mouse or dragging some UI element?
I suppose the principle could be applied 3 dimensionally, but then it seems to require the target have some depth W that you were attempting to stop within.

Looks like someone's "helping" you along.

Sips jumbo coffee.
 
Very interesting thread. While I'm sure a mini iPad would please *some* people, I generally agree with what the OP is trying to say. I don't think there's room for another form factor between smartphones and iPad-size tablets.

Don't get me started on the ridiculous Galaxy Note!

Anyway, Apple will do what they choose to do. I'm sure they've got some brilliant minds working on the idea. Jobs did say that they'd spent a large amount of time and effort researching the different sizes and settled on 9.7" as optimum, so I'd be very surprised if they went back on that.

Like any company, however, Apple makes the occasional mistake. I'm not necessarily saying a mini iPad would be a mistake, but if it comes to light and ends up as one, all they'd need to do is scrap it. Apple can afford to gamble a bit!
 
12 pages of Apple fanbois fighting over what Google is doing now and what Apple will or will not do. Just think about that for a minute. Let it soak in.
 
Regardless of what Jobs said

So you're saying Steve Jobs was wrong then. It seemed like that quote was fairly important to you considering how many times you brought it up.
All your points seem to curiously wind up going down in flames.


So another way of saying it is that since the entire UI is scaling down at this rate, you'd have to sand 1/4 of your fingers down to account for the loss of the UI size.

There's already a large number of 7" tablets that have been sold. You're saying the owners all need to sand down their fingers?
What size do they need to abrade them down to? A percentage is not a number.
Must all fingers be ground down?
Are you saying children's fingers should be ground down???
What a horrible thing!

"Be a good boy"
 
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"Poor product" is an unfair characterization. It was fair value for what they charged. They packed a decent amount of technology into a $200 package. It wasn't going to offer the iPad experience but it wasn't designed to.

No I am sorry I agree. It wasn't a poor product for the price point but it was for what people were expecting. A lot of these people were essentially expecting a mini iPad from all of the "iPad killer" hype and that is obviously not what they got. But my point was that I think it does show a market for this category. If apple could come out with something for it that worked, the initial demand would be high and then because it really would be an iPad mini...it would continue. But then you would have to call the iPad mini an "iPad killer" as well and apple would have to use inferior technology in it to prevent themselves from ruining their own sales on regular iPad.
 
12 pages of Apple fanbois fighting over what Google is doing now and what Apple will or will not do. Just think about that for a minute. Let it soak in.

If you haven't actually read the thread, try doing so.
If you have read it, apparently you have about the comprehension skills as freudling.
Just think about that a minute.
Try and let it soak in.
 
The reason why it failed and the reason why every single tweener has failed is for the reasons I keep mentioning. It's a dead category: nobody needs it. Nobody needs it because it's worse at pretty much everything compared to a smartphone and an iPad 9.7. The sooner you realize the this, the clearer the picture becomes.

For the most part haven't all non iPad tablets failed regardless of screen size?

Since I am assuming your "argument" is valid, that means there is a tweener with software that can measure up to the iPad...please let me know which one it is because I want it.
 
from the wiki:
W is the width of the target measured along the axis of motion.

If so, how could D be perpendicular to the surface?
Doesn't this statement imply that the axis of motion must be in the same plane as the target; e.g. moving a mouse or dragging some UI element?
I suppose the principle could be applied 3 dimensionally, but then it seems to require the target have some depth W that you were attempting to stop within.

It depends on how your finger moves when trying to hit the target. If you're dragging something on the screen - you are moving along the screen surface. If you're tapping a button - your axis of motion is 3-dimensional.

In either case, the difference between 9.7" and 7.85" screens is around 20%, and so "D" will be scaled accordingly.

If we consider the simplest example where you drag from one corner of the screen to another (so D is 9.7 and 7.85 respectively) - the Fitts ID in case of large iPad is 4.92, and in case of iPad Mini is 4.91. Practically the same.

So you can take "iPad Mini won't work because of Fitts" argument and flush it down the toilet.. right where the rest of the arguments against iPad Mini viability already ended up throughout this thread.
 
So you can take "iPad Mini won't work because of Fitts" argument and flush it down the toilet.. right where the rest of the arguments against iPad Mini viability already ended up throughout this thread.
You know, I wasn't defending the Fitts Argument; I am largely in agreement with you.


If you're tapping a button - your axis of motion is 3-dimensional.
But then since the target is 2-dimensional, W would approach zero if you measure the target along the axis of motion.

It appears that by definition, Fitts' Law is not relavent to this type of action or viewing distance.
 
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If you haven't actually read the thread, try doing so.
If you have read it, apparently you have about the comprehension skills as freudling.
Just think about that a minute.
Try and let it soak in.

knucklehead: consolidating the meaning of that name each and every day.

But yes, people should read the thread.

----------

Very interesting thread. While I'm sure a mini iPad would please *some* people, I generally agree with what the OP is trying to say. I don't think there's room for another form factor between smartphones and iPad-size tablets.

Don't get me started on the ridiculous Galaxy Note!

Anyway, Apple will do what they choose to do. I'm sure they've got some brilliant minds working on the idea. Jobs did say that they'd spent a large amount of time and effort researching the different sizes and settled on 9.7" as optimum, so I'd be very surprised if they went back on that.

Like any company, however, Apple makes the occasional mistake. I'm not necessarily saying a mini iPad would be a mistake, but if it comes to light and ends up as one, all they'd need to do is scrap it. Apple can afford to gamble a bit!

If Apple releases a Mini, 6 months later people will be calling for Tim Cook's resignation.

----------

"Be a good boy"

So you're saying Steve Jobs was wrong then. It seemed like that quote was fairly important to you considering how many times you brought it up.
All your points seem to curiously wind up going down in flames.


The only thing going down is flames is you.

There's already a large number of 7" tablets that have been sold. You're saying the owners all need to sand down their fingers?
What size do they need to abrade them down to? A percentage is not a number.
Must all fingers be ground down?
Are you saying children's fingers should be ground down???
What a horrible thing!


They should use a cheese grater.

----------

For the most part haven't all non iPad tablets failed regardless of screen size?

Since I am assuming your "argument" is valid, that means there is a tweener with software that can measure up to the iPad...please let me know which one it is because I want it.

All non-iPads have pretty much failed in the market.

But that doesn't mean an ADDITIONAL sub-category of tablets is viable at all. In other words, if you haven't seen the conclusions in this thread, Apple could make the nicest screened, fastest tablet ever in a tweener size and it would fail because there's no market for a middle tablet category.
 
If Apple releases a Mini, 6 months later people will be calling for Tim Cook's resignation.

There are always people calling for his resignation. Will they be clever, informed people who own stock and/or sit on the board or work as stock analysts?

No. Then, as now, they'll be uninformed twits.
 
It depends on how your finger moves when trying to hit the target. If you're dragging something on the screen - you are moving along the screen surface. If you're tapping a button - your axis of motion is 3-dimensional.

In either case, the difference between 9.7" and 7.85" screens is around 20%, and so "D" will be scaled accordingly.

If we consider the simplest example where you drag from one corner of the screen to another (so D is 9.7 and 7.85 respectively) - the Fitts ID in case of large iPad is 4.92, and in case of iPad Mini is 4.91. Practically the same.

So you can take "iPad Mini won't work because of Fitts" argument and flush it down the toilet.. right where the rest of the arguments against iPad Mini viability already ended up throughout this thread.

In the running discussions, the iPad Mini has the exact same button sizes as iPhones on a much larger screen. The buttons are not scaling proportionally to the increased screen size according to the button size spectrum derived from Apple's Guidelines. These guidelines consider many variables, which are focused on the distance the device is held from the face and the surface area of the device. The buttons need to be bigger than the iPhone's because the screen is larger and the device is held further from your face. The farther it's held from the face, the harder it is to accurately hit buttons of the same size.

Taking the logical DPI of an iPhone... being the same as the Tweener, scaling an App from the Tweener to fit the iPhone would result in the buttons themselves becoming less than half as big, ~.12" instead of the required 0.27".

Everything gets smaller and closer together when you scale Apps down as proposed. As Jobs notes:

There are clear limits of how close you can physically place elements on a touchscreen before users cannot reliably tap, flick or pinch them. This is one of the key reasons we think the 10-inch screen size is the minimum size required to create great tablet apps.

All of the screen elements get closer together when they scale down to smaller screen sizes with the same logical DPI. The UIs and content start breaking down. This is what happens on Tweeners when you scale Apps down from say an iPad 9.7.

Tweeners UIs must be tweaked and changed to account for their screen size.

To demonstrate how this is so, load a PDF on your iPad and then load it on your Tweener. You'll see the PDF page on the iPad fairly well to the point where you could read it without pinching and zooming in. But on the Tweener, the page gets scaled down to the point where it's difficult to read without pinching and zooming.

I've done hard testing with Apps scaled down on the iPad to tweener sizes. Pages, Safari, Facebook...

In Safari for instance:

1. Buttons are too close together and too small to the point that my fingers were over top of two buttons at once in different areas.

It turns out there is a very fine margin of error on these devices for the distance upon which buttons are from each other and their size.
 
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Taking the logical DPI of an iPhone... being the same as the Tweener, scaling an App from the Tweener to fit the iPhone would result in the buttons themselves becoming half as big, or .135" instead of the required 0.27".

I can't figure out if you're really this dense, or just trolling at this point..

Apps from "Tweener" would never need to scale down to iPhone size. The logical resolution of Mini is 1024x768. The logical resolution of iPhone is 320x480. The apps are not interchangeable obviously.

The relevant case of Apps scaling down is from 9.7" iPad to 7.85" iPad (same logical resolution). You take the same app developed for 9.7" iPad and you run it on 7.85" iPad. The buttons scale down from 0.33" to 0.27". Everything is still within Apple UI guidelines and everything still workable even according to Fitts (as I demonstrated in my earlier posts).

Do you get this into this thick skull of yours yet?
 
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Taking the logical DPI of an iPhone... being the same as the Tweener, scaling an App from the Tweener to fit the iPhone would result in the buttons themselves becoming less than half as big, ~.12" instead of the required 0.27".

I can't figure out if you're really this dense, or just trolling at this point..

While true, it appears to be just a crazy irrelevant strawman argument.
See Chewbacca Defense
 
I can't figure out if you're really this dense, or just trolling at this point..

Apps from "Tweener" would never need to scale down to iPhone size. The logical resolution of Mini is 1024x768. The logical resolution of iPhone is 320x480. The apps are not interchangeable obviously.

The relevant case of Apps scaling down is from 9.7" iPad to 7.85" iPad (same logical resolution). You take the same app developed for 9.7" iPad and you run it on 7.85" iPad. The buttons scale down from 0.33" to 0.27". Everything is still within Apple UI guidelines and everything still workable even according to Fitts (as I demonstrated in my earlier posts).

Do you get this into this thick skull of yours yet?

Are you really that dense that you don't understand what you are saying and what I am saying? You seriously don't see the flaw in your conclusions?

Apple doesn't say anything about a button size of .27" on a 7.85" screen because that screen size doesn't exist. The way their screen resolutions are on different devices, the guidelines are clear. But Apple would never put a guideline in place to make buttons on a device with a massive increase in size and surface area the same size as a tiny iPhone because the button size MUST account for the size of the device and the distance upon which it's held from the face.

Therefore, .27" is not the right size. It MUST be bigger on the Tweener.

As for scaling, the DPI in the discussions of the Tweener is 163 DPI, the original iPad is 132 DPI. They both have the same resolution of 1024 x 768. What people have done is scaled down Apps with ZERO UI changes to the Tweener from the iPad 9.7: everything gets smaller because of the higher DPI.

Further scaling down the App to fit the iPhone screen, a screen with the same DPI... although it would look hacked, the button sizes would become so small it would be absurd. It illustrates the point of the disproportionate problem of just scaling down Apps like this.

The point: you can't just scale down an iPad App to fit a smaller screen like a Tweener without making any changes. The UI becomes disproportionate to what the device requires in terms of button sizes, spacing between buttons, the distance the device is held from your face, the surface area, etc.

Thus, Tweeners UI's must be tweaked and changed to account for the size of the device.
 
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