Ben Shneiderman recalled that "Tim told me at the time that he was influenced by our design as he saw it in the Hypertext on Hypertext project".

Ben Shneiderman wrote the following email to John Gilmore and I, in response to a question John asked me about the origin of the term "hyperlink" raised in a discussion on the Internet History mailing list. John then forwarded Ben's email to the Internet History mailing list, here:

https://elists.isoc.org/pipermail/internet-history/2020-Apri...

>My students conducted more than a dozen experiments (unpublished) on different ways of highlighting and selection using current screens, e.g. green screens only permitted, bold, underscore, blinking, and I think italic(???). When we had a color screen we tried different color highlighted links. While red made the links easier to spot, user comprehension and recollection of the content declined. We chose the light blue, which Tim adopted.

>His systems with embedded menus (or hot spots), where a significant user interface improvement over early systems such as Gopher. But Tim told me at the time that he was influenced by our design as he saw it in the Hypertext on Hypertext project that we used Hyperties to build for the July 1988 CACM that held the articles from the July 1987 Hypertext conference at the University of North Carolina. The ACM sold 4000 copies of our Hypertext on Hypertext disks.

Here's some more information about High-Precision Touchscreens, 1988-1991 HCIL Research, which may be what whoever mis-quoted Ben about inventing the iPhone keyboard was actually referring to. Specifically, Ben and his students developed the "Lift-Off Strategy" and other visual feedback techniques that made it possible to precisely select small targets on touch screens. Below, he simply and truthfully stated that "the iPhone uses a lift-off strategy", not that he invented the iPhone keyboard.

At the time, touchscreens were notorious for being hard to use, and they usually triggered on the location you initially touched the screen, instead of giving preview feedback when you touched, and letting you change the selection while providing visual feedback before lifting off and selecting something like a key or text or pixel.

Also, the precision touch screen work at HCIL was cited as prior art in legal cases contesting the Apple patents related to the "Slide to Unlock" touchscreen slider that unlocks the iPhone.

https://www.cs.umd.edu/hcil/touchscreens/

[...]

During 1989-1991, we worked on a home automation system and explored several direct manipulation designs (e.g. clocks and calendars to schedule devices to go on and off, ON-OFF switches with buttons or sliders) . A playful fingerpainting exploration tool and toy called Playpen was developed. Finally we worked with National Cash Register (NCR) to explore how touchscreens might be used to replace keyboards when store cashiers needed to enter a little bit of data about shopppers (such as phone numbers or addresses). We stopped doing research on touchscreens as successful applications found their ways in museums or cash registers. Pen interfaces, made popular by the Palm Pilots, continued the work as they afforded a similar sense of "real" direct manipulation. Eventually touchcreens came back as the input device of choice of mobile devices, especially after the launch of the iPhone is 2007.

For a quick summary of our work refer to:

Shneiderman, B. (March 1991), Touch screens now offer compelling uses,
IEEE Software 8, 2, (March 1991) 93-94, 107.
Also in Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 187-193.

http://www.cs.umd.edu/hcil/trs/91-02/91-02.pdf

For a longer review of the state of the art of touchscreen use at that time see:

Sears, A., Plaisant, C., Shneiderman, B., A new era for high-precision touchscreens (1990 tech report),
CS-TR-2487, CAR-TR-506
Later published in Advances in Human-Computer Interaction, vol. 3, Hartson, R. & Hix, D. Eds., Ablex (1992) 1-33.

http://www.cs.umd.edu/hcil/trs/90-01/90-01.pdf

We produced the first HCIL Video Report in 1991 by recording the demonstrations from 1988-1991 (most are now on YouTube and embedded below). Those videos were given along with copies of our papers to all the sponsors of the lab, and attendees of the annual HCIL symposium. The videos were available for sale, and have been used extensively in HCI classes. Many were also published as part of the ACM CHI videos.

http://www.cs.umd.edu/hcil/pubs/video91.shtml

Between 1988 and 1993 Apple was a sponsor of the HCIL lab, Steve Jobs visited in person in 1988, and Ben Shneiderman was a consultant for Apple at several occasions. Demos were also shown to our lab's visitors, and videos shown during invited lectures at conferences or during industry visits (see Ben Shneiderman's resume for a partial list)

From bad reputation to high precision touchscreen

In 1987 (and still long afterwards) touchscreens had the bad reputation of being imprecise. Most user interface books would state that touchscreens selections were "of course limited to targets larger than the average finger". To use touchscreens for browsing information systems such as Hyperties, we had to be able to select small targets (e.g. the letters of the alphabets of the index table of content). At the time, all touchscreens selections were done in such a way that a target was selected as soon as the finger came over it, and the corresponding action was performed immediately (we called it "first touch" or "land-on" strategy). Errors were common, due to parallax or calibration problems, and users were frustrated when the wrong target was repeatedly selected by mistake.

Lift-Off strategy

A first breakthrough was to propose an alternative technique for selection: the lift-off strategy. As users touch the screen, feedback is provided as to what will be selected and the action takes place when the finger is lifted off the screen. In our implementation a cursor was drawn on the screen slightly above the finger. When the cursor was over a target, the target was highlighted. Users could then either lift-off their finger to select the highlighted target, or adjust their position by sliding their finger to a neighboring target. This was a major breakthrough: only the cursor position mattered for the selection, not the finger itself. Selecting a single character was now possible.

The touchscreen technology has greatly improved but overall the lift-off strategy is still useful (e.g. the iPhone uses a lift-off strategy.)

88-04 Potter, R.L., Weldon, L.J., Shneiderman, B. (May 1988).
Improving the accuracy of touch screens: an experimental evaluation of three strategies,
Proc. of the Conference on Human Factors in Computing Systems, CHI `88 (Washington, DC) 27-32.
Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 161-169.

High-Precision touchscreen: the next step was to try to stabilize the touchscreen so that the cursor would stay put when the finger didn't move. This was accomplished with a clever time-dependant averaging of the positions returned by the device. Now, individual pixels could be selected (in the 480x350 high resolution screen of the time). An experiment showed that there was significant difference in selection times and error rates between mouse and touchscreen for targets down to about 1mm2, when using a lift-off strategy with a stabilized touchcreen. Companies such as Elographics and Microtouch, with whom we had good relations, integrated stabilization techniques into the drivers of their touchscreens. From then on, high-precision was possible, and designers could do everything with the touchscreen that they could do with the mouse.

89-17 - Sears, A., Shneiderman, B. (June 1989)
High precision touchscreens: design strategies and comparisons with a mouse,
International Journal of Man-Machine Studies, (1991) 34, 4, 593-613.
Also Sparks of Innovation in Human-Computer Interaction, Shneiderman, B., Ed., Ablex (June 1993) 171-185.

[...]

Toggles (buttons, sliders, rockers etc.),

In 1990 we designed and compared a series of touchscreen toggle switches allowing devices to be switched ON or OFF. The designs included button type toggles and sliding toggles.

This video was distributed to the attendees of the 1991 Human-Computer Interaction Laboratory Open House on June 7, and later on published in the SIGGRAPH Video Review, Issue 77 corresponding to the CHI '92 Technical video program.(see the accompanying CHI'92 Proceeding short paper). The video and its short paper are now being cited as prior art in legal cases contesting the Apple patents related to the "Slide to Unlock" touchscreen slider that unlocks the iPhone.

http://dl.acm.org/citation.cfm?id=143079

http://www.cafc.uscourts.gov/sites/default/files/opinions-or...

Designed originally for home automation, those toggles were also later used in a NASA design toolkit. Now slider designs can be found everywhere in touchscreen-based smartphones (such as the first iPhone in 2007). As we mentionned in our paper and video a slider design is more secure so that the phone cannot be turned on by mistake. A click confirms the action. Any design that enforces a sliding gesture would achieve a similar goal.

90-08 Plaisant, C., Wallace, D. (Nov. 1990)
Touchscreen toggle switches: push or slide? Design issues and usability study,
CS-TR-2557, CAR-TR-521

http://www.cs.umd.edu/hcil/trs/90-08/90-08.pdf

[...]

1991 Video Reports

http://www.cs.umd.edu/hcil/pubs/video91.shtml