Case Study Designing the Palm Pilot

The ZoomerShort for the word "Consumer"Developed by Tandy and CasioMet Donna DubinskyAOL and Intuit came onboard...It had many interesting data features,but it was slow, had bad text recognition,and became one of the first majorhandheld flops. Between October 1993and January 1994, it had sold only10,000 units.The First Attempt -the ZoomerDesign by CommitteeUnderpoweredToo much softwareVictim of FeatureCreepOther PDAAt the same time, the Apple Newton wasreleased, but didn't do very well. All thePDAs at the time were too big andoverpriced.So Hawkins measured his shirt pocket.The goal: small, simple, and less than$300 dollars.The Original Prototype Redone in Plastic EvolutionThe ResultThe Palm Pilot became one of thefastest-selling high-tech devices of thedecade.Over time Hawkins left Palm, developedVisor, and then returned to Palm.OtherIdeasChapter 5Software Tools

PrototypingProcessPresentation / EvaluationPaper StoryboardEach Team member creates a designEach Member presents their designPaper Prototypes Paper Prototypes Wireframe ModelCreated in PowerPointLoFi Prototype HiFi Prototype Why Build Prototypes?Must test ideas with usersPaper mock-ups no good enoughnot realistic of how interface will beusedBuilding final app. now is a mistakechanges in the UI can cause hugecode changestakes too much timeDrag & drop prototyping tool

Why use Tools (rather than code)?FasterEasier to incorporate test changesMultiple UIs for same applicationConsistent user interfacesEasier to involve variety of specialistsSeparation of UI code from app. codeeasier to change/maintainMore reliableUser Interface DevelopmentEnvironmentsSpecification MethodsProgramming Support ToolsDesign Tools for Evaluating andCritiquingSpecification MethodsNatural LanguageFormal, Semi-Formal LanguageMultiparty GrammarsMenu TreesTransition DiagramsState ChartsUser Action NotationNatural LanguageSpecifications tend to be:lengthyvagueambiguousOften are difficult to prove:correctconsistentcompleteBackus-Naur Forma.k.a. Backus Normal Form/BNFHigh-level components are described asnon-terminalsSpecific strings are described asterminalsGrammars Example::= ::= , ::= ::= ::= | ::= A - Z::= () -::= ::= ::= ::= 0|1|2|3|4|5|6|7|8|9Examples of acceptable entries- WASHINGTON, GEORGE (301)555-1234- BEEF, STU (726) 768-7878- A, Z (999) 111-111BNF ExampleUnix Command-Copying Files (cp)cp [ -ip ] filename1 filename2cp -rR [ -ip ] directory1 directory2cp [ -iprR ] filename ... directory[ ]'s = 0 or more timesMultiparty GrammarsSpecify a role (U=user, C=Computer) ::= ::= login ::= ::= Hello []login larryHello larry

Transition DiagramsProgramming Support ToolsScreen MockupsPrototyping ToolsProgramming ToolkitsUser Interface Management SystemsSample ToolsSILKVisual StudioIBasicPowerPointSILK (now Demin)Sketching Interfaces Like KrazyVisual Studio (BASIC / C++...)Lots of Widgets - DemoEasy to UseCan evolve to applicationIBASICSimilar to Visual BASIC30 day trialFull version only 30 dollarsLimited widgetsPowerPointCan be a useful prototyping toolbecause it offers a good compromisebetween paper and "electronic"sketches or prototypes.+ Is fairly fast and flexible+ Has tools and objects+ Can perform simple actions- Limited features- Porting problemsConsiderationsPerformanceprototyping tools produce slowprogramsWidgetsPrototyping tools may not havecomplete setWidget set common to platformFinal product?New DesignWhiteboard -> Paper -> PowerPoint ->Screen Images -> PrototypeRedesignScreen Dumps -> Whiteboard/Paper ->Screen Images -> Prototype/PowerPoint

Design Tools for Evaluation andCritiquingText Analysis ToolsSpell checkingGrammar AnalysisDisplay Analysis ProgramTullis' Display Analysis ProgramTakes alphanumeric screens andproduces display-complexity scoreUpper-case letters: 77% The percentage ofupper-case letters is high. Consider usingmore lower-case letters, since text printed innormal upper- and lower-case letters is readabout 13% faster than text in all upper case.Reserve all upper-case for items that need toattract attention.Example ContinuedMaximum local density = 89.9% at row 9,column 8. Average local density = 67.0%The area with the highest local density isidentified...you can reduce local density bydistributing the characters as evenly as feasibleover the entire screen.Total layout complexity = 8.02 bitsLayout complexity is high.The Design ChallengeThe TelephoneThe Typewriter“It probably won a prize”Fast Food RestaurantsThe Design ChallengeDesigners are not typical usersProgrammers are not eitherClients may not be usersDesign for Special PeopleIssuesCreeping FeaturismThe Tyranny of the Blank ScreenHow to do things WrongMake things invisibleBe arbitraryBe InconsistentMake Operations UnintelligibleBe ImpoliteMake Operations DangerousGroup TimeWorking on experimentsNext week, start on prototypesNew groups?Same Groups?End of This Lesson