# Navigation in Long Forms on Smartphones: Scrolling Worse than Tabs, Menus, and Collapsible Fieldsets

Johannes Harms, Martina Kratky, Christoph Wimmer, Karin Kappel, Thomas Grechenig

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## To cite this version:

Johannes Harms, Martina Kratky, Christoph Wimmer, Karin Kappel, Thomas Grechenig. Navigation in Long Forms on Smartphones: Scrolling Worse than Tabs, Menus, and Collapsible Fieldsets. 15th Human-Computer Interaction (INTERACT), Sep 2015, Bamberg, Germany. pp.333-340, 10.1007/978-3-319-22698-9_21. hal-01609423

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# Navigation in Long Forms on Smartphones: Scrolling worse than Tabs, Menus, and Collapsible Fieldsets

Johannes Harms, Martina Kratky, Christoph Wimmer, Karin Kappel, Thomas Grechenig

INSO Research Group, Vienna Univ. of Technology, Austria.
[firstname].[lastname]@inso.tuwien.ac.at

**Abstract.** Mobile applications provide increasingly complex functionality through form-based user interfaces, which requires effective solutions for navigation on small-screen devices. This paper contributes a comparative usability evaluation of four navigation design patterns: Scrolling, Tabs, Menus, and Collapsible Fieldsets. These patterns were evaluated in a case study on social network profile pages. Results show that memorability, usability, overview, and subjective preference were worse in Scrolling than in the other patterns. This indicates that designers of form-based user interfaces on small-screen devices should not rely on Scrolling to support navigation, but use other design patterns instead.

**Keywords.** Navigation; Mobile; Smartphone; Form Design; Evaluation

## 1 Introduction

Forms are widely employed as user interfaces (UIs) for data entry and subsequent editing [15, 17, 22]. Long forms are often considered a bad design practice – e.g., an empirical study [22, p. 294] and recent guidelines [3] recommend against long forms and unnecessary questions. But they cannot always be avoided due to complex application requirements [16]. This also holds for forms on small-screen, mobile devices such as smartphones. Examples of mobile apps with long form-based UIs include editing a contact in the iOS address book (43 form fields), Facebook's mobile profile page (11 collapsible fieldsets for 88 form fields), and the Samsung Galaxy system settings (4 tabs for about 380 form fields). The length of these UIs clearly indicates a need for effective navigation. This can be supported through a variety of navigation design patterns (NDPs). Popular NDPs – also employed in the above-mentioned apps – include Scrolling, Tabs, Menus, and Collapsible Fieldsets. It is the goal of this work to compare and evaluate these four NDPs in a case study on social network profile page editing, see Fig. 1 for screenshots of the evaluated prototypes. The remainder of this work is structured as follows. Section 0 discusses related work with a focus on navigation within mobile UIs. Section 3 describes the case study and the empirical study design. A comparative, lab-based usability test was conducted with N=24 participants. Evaluation results are presented in Sections 4 and 5.
<figure><img src="image_3.png" /><figcaption>**Fig. 1.** Screenshots of the four navigation design patterns (NDPs) evaluated in this work: Scrolling (a) shows the entire form in a single, static view. Tabs (b) and Menus (c) provide an overview of the form schema and show details (for the selected tab or menu entry) in a spatially separated view. Collapsible Fieldsets (d) were designed as described in [16]; they employ the Focus+Context principle by surrounding detailed information at the user's focus of interest with a contextual overview.</figcaption></figure>

## 2 Related Work

A recent overview of navigation research in HCI in mobile, wearable, embedded, 3D, and desktop information systems is provided in [20]. One branch of research has examined navigation between documents, e.g., in hypertext environments [8] and websites [21]. In contrast, research on within-document navigation investigates topics such as reading long documents [1, 2, 13], navigation in lists [12], and navigation in long form-based UIs [11, 16], as examined in this paper. Mobile UIs require special solutions for navigation – techniques for desktop computers may not be directly applicable [23]. Challenges specific to mobile navigation include smaller screen sizes, limited input devices and changing external environment [9].

Related work has presented recommendations for websites on smartphones, suggesting to keep navigation on a minimal scale to avoid using up too much screen space [18]. Existing navigation design patterns (NDPs) can be classified through concepts from information visualization [10]. Accordingly, Tabs, Menus, and Tables-of-Contents offer a spatially separated overview and detailed view. Zooming (not examined in this work) uses a temporal separation. Collapsible Fieldsets employ the Focus+Context principle, seeking to minimize the separation by combining overview and detail in a single, dynamic view. In contrast, Scrolling uses a single, static view.
Related evaluations of NDPs have compared the following usability measures: ef-
fectiveness and efficiency, errors, simplicity, comprehensibility, learnability, memo-
rability, and user satisfaction; albeit with conflicting results, see [23] for a literature
review. Scrolling is a popular NDP, but has delivered bad results for long mobile UIs
[14]. Tabs are a common way to organize navigation in both desktop and mobile in-
terfaces. They have been suggested for splitting heterogeneous content [19, p.448],
but also recommended against due to poor performance in very long forms [17, p.111]
[19, p.357]. Collapsible Fieldsets and Fisheye distortions employ the Focus+Context
principle, which has been shown to reduce task completion time when navigating
websites on small-screen devices [14]. The Fisheye distortion that is often – but not
necessarily [10] – used in Focus+Context UIs has been shown to decrease targeting
performance [10, 14]. Hence related work has recommended to investigate new, non-
traditional, possibly non-distorted Focus+Context interaction techniques [4]. Within
this direction, recent work has proposed a non-distorted, adaptive form design featur-
ing Collapsible Fieldsets [16]; one such design is evaluated in this work with regard
to small-screen devices. Menus and Tables-of-Contents are employed in many mobile
apps to provide overview and detail for the primary navigation. Despite the popularity
of these patterns, related research has mostly investigated Overview+Detail in a dif-
ferent context, namely navigation in two-dimensional map views. One study reported
benefits [6], another pointed out the drawback of reduced screen size [7]. In summary,
the above conflicting results indicate a need for further evaluation.

3 Case Study: Social Network Profile Forms

Social network profile pages were chosen as a case study. Many popular social
networks allow users to edit their profile using a mobile app installed on their
smartphone. These profile pages employ long form-based user interfaces (e.g., Face-
book's profile page with 88 form fields, LinkedIn's with 43 fields) to help users pro-
vide details about themselves. Tasks comprise both initial filling and subsequent re-
vising. In this respect profile pages are similar to forms in productivity applications
and different from, e.g., registration forms and questionnaires. The forms are sparsely
filled because not all fields are relevant, the frequency of use is rather low, and infor-
mation is shared voluntarily at the users' discretion. Navigation is non-linear, not
strictly goal-directed (compare [13] for more on goal directedness), and to some de-
gree explorative. In contrast to other domains, no special knowledge is required to
answer the questions of a profile page, making the case study suited for evaluation
without interference by varying domain-specific knowledge.

The four NDPs of Scrolling, Tabs, Menu, and Collapsible Fieldsets served as test conditions, see Fig. 1a-d for screenshots. We measured efficiency, errors, memorability, perceived usability, and subjective rankings of difficulty, overview, and preference. Participants started working with one randomly assigned NDP. A subsequent first questionnaire assessed memorability (between-subject test design). They then performed three more test runs with the remaining three NDPs. The order in which NDPs were assigned was randomized to level out learning effects. This provided
measures regarding efficiency and errors (within-subject test design). Lastly, partici-
pants ranked and qualitatively described the NDPs in a second post-test questionnaire
and in a short, semi-structured interview (between-subject). All tests took place in a
home/office usage context. Users were allowed to sit or stand and used their own
smartphones to access a website running the profile page. The tasks required entry,
retrieval, editing, and deletion of fictitious form data. Screen recordings and log files
supported further analysis.

4 Results

This section presents quantitative and qualitative results, as assessed through a
comparative usability test with N=24 participants (f=14, m=10). The significance of
observed differences was tested using two-sided Kruskal-Wallis H-Tests with a sig-
nificance level of p<0.05. We used an Exact-Methods implementation of Kruskal-
Wallis when computationally possible, otherwise Monte-Carlo with 10.000 samples.
Post-hoc pairwise comparisons between groups were tested using Exact Mann-
Whitney U-Tests. These test methods are well-suited for the lack of normality and the
heteroscedasticity present in much of the data.

**Efficiency:** We measured the time needed for navigation by analyzing screen record-
ings, thus splitting total task completion time into navigation, data entry, and task
comprehension. There were no significant influences of NDP on the time needed for
navigation (p=0.170), data entry (p=0.994), and task comprehension (p=0.377), see
Table 1. To assert that these results are not biased by learning effects, we additionally
conducted separate statistical tests for each one of the test runs 1-4, but found no sig-
nificant differences. This indicates that our randomized study design worked well for
eliminating learning effects.

**Navigation Errors:** Screen recordings were further analyzed in order to count navigation errors. This included Scrolling in the wrong direction as well as selecting the wrong Tab, Menu entry or Fieldset. We found no significant influence (p=0.094) of NDP on the number of errors, see Table 2.

**Memorability.** The first questionnaire allowed to measure three memorability scores. Mem1 (number of correctly remembered form sections) and Mem2 (number of correctly ordered form sections) relate to how well participants remembered an overview of the form schema, whereas Mem3 (number of correct labels from the “hobbies” section) measures how well they remembered details. Test results show a significant influence of NDP on Mem1 (p=0.001), but not on Mem2 (p=0.128) and Mem3 (p=0.813), see Table 3. Pairwise comparisons for Mem1 revealed that Menu worked significantly better than both Collapsible Fieldsets (p=0.009) and Scrolling (p=0.002), the latter of which performed worse than Tabs (p=0.041); all other differences were insignificant.
<table><caption>**Table 1.** Efficiency (measured as time needed for navigation, data entry, and task comprehension) was insignificantly different depending on NDP.</caption><thead><tr><th>Time needed for:</th><th>Navigation</th><th>Data Entry</th><th>Task comprehension</th></tr></thead><tbody><tr><td>Scrolling</td><td>00:59.37 ± 00:18.56</td><td>01:25.63 ± 00:38.03</td><td>00:41.79 ± 00:15.28</td></tr><tr><td>Tabs</td><td>00:53.74 ± 00:30.14</td><td>01:18.93 ± 00:25.27</td><td>00:49.26 ± 00:17.77</td></tr><tr><td>Menu</td><td>01:05.50 ± 00:27.80</td><td>01:22.92 ± 00:32.79</td><td>00:45.04 ± 00:15.39</td></tr><tr><td>Collapsible Fieldsets</td><td>00:59.15 ± 00:25.00</td><td>01:18.40 ± 00:20.62</td><td>00:41.05 ± 00:13.23</td></tr><tr><td>H-Value, p-Value</td><td>H(3)=4.967, p=0.170</td><td>H(3)=0.83, p=0.994</td><td>H(3)=3.144, p=0.377</td></tr></tbody></table>

<table><caption>**Table 2.** Navigation errors were not significantly different depending on NDP.</caption><thead><tr><th>Navigation Errors</th><th>Scrolling</th><th>Tabs</th><th>Menu</th><th>Collapsible Fieldsets</th><th>H-Value, p-Value</th></tr></thead><tbody><tr><td></td><td>2.50 ± 1.719</td><td>1.75 ± 2.541</td><td>1.79 ± 2.553</td><td>2.00 ± 2.377</td><td>H(3)=6.333, p=0.094</td></tr></tbody></table>

<table><caption>**Table 3.** Memorability scores depending on NDP. Mem1 (number of correctly remembered form sections) was significantly better for Menu, followed by Tabs, Collapsible Fieldsets and Scrolling. Mem2 (correctly ordered form sections) and Mem3 (correctly remembered labels in the “hobbies” section) showed no significant differences.</caption><thead><tr><th>Memorability Scores:</th><th>Mem1</th><th>Mem2</th><th>Mem3</th></tr></thead><tbody><tr><td>Scrolling</td><td>1.00 ± 1.265</td><td>3.17 ± 0.753</td><td>1.50 ± 0.548</td></tr><tr><td>Tabs</td><td>3.67 ± 1.966</td><td>3.67 ± 2.338</td><td>1.50 ± 0.837</td></tr><tr><td>Menu</td><td>4.50 ± 0.548</td><td>4.67 ± 1.633</td><td>1.83 ± 0.753</td></tr><tr><td>Collapsible Fieldsets</td><td>2.50 ± 1.225</td><td>4.83 ± 0.983</td><td>1.83 ± 1.169</td></tr><tr><td>H-Value, p-Value</td><td>H(3)=13.071, p=0.001</td><td>H(3)=5.616, p=0.128</td><td>H(3)=1.072, p=0.813</td></tr></tbody></table>

**Perceived Usability.** Participants comparatively rated the usability of the four NDPs by answering System Usability Scale (SUS) [5] questions in the second post-test questionnaire (handed out upon completion of all test runs 1-4). Overall SUS scores significantly differed (p=0.019) depending on NDP, see Table 4. Pairwise comparisons showed that Scrolling scored significantly worse than both Tabs (p=0.007) and Menu (p=0.024). We also evaluated each SUS question individually, revealing significant influences of NDP on three out of ten questions: SUS1 (p=0.001, “I think that I would like to use this design frequently”), SUS5 (p=0.015, “I found the various functions in this design were well integrated”), and SUS8 (p=0.004, “I found the design very cumbersome to use”), see Table 4. In every one of these questions, pairwise comparisons showed that Scrolling performed significantly worse than all other NDPs (p-Values between 0.000 and 0.026); all other pairwise differences were insignificant.

**Subjective Rankings.** Users ranked clarity of overview, perceived difficulty, and their individual preference of the four NDPs in the second post-test questionnaire. Results show a significant influence of NDP on overview (p<0.001) and preference (p=0.001), but not on difficulty (p=0.143), see Table 5. Pairwise comparisons for both preference and overview revealed that Scrolling worked significantly worse than all of the other NDPs (all p-Values ≤ 0.001); there were no significant differences in all other pairwise comparisons.
**Qualitative feedback.** Semi-structured post-test interviews asked participants to describe their experience and whether they had difficulties using the NDPs. The interviews were recorded, transcribed and analyzed using empirical codes, see Table 6. Scrolling garnered more negative comments than any other NDP. Users criticized a lack of usability in Scrolling (N=17 comments), stating they found it disorienting and cumbersome. In the same way, they criticized a lack of overview (N=7). In contrast, the other three NDPs received mostly positive comments regarding these topics. Tabs (N=2) and Menu (N=4) were criticized for hidden UI elements, i.e., the tab bar or menu button was hidden when users scrolled down. The visual design was only commented upon with regard to Collapsible Fieldsets (N=6); some users mentioned a lack of color; others were unable to articulate more specifically what they did not like. Users also complained that Collapsible Fieldsets (N=2) and Menu (N=3) lacked familiarity.

<table><caption>**Table 4.** Perceived usability. Overall SUS (System Usability Scale) scores ranging from 0 to 100, the higher the better. Three individual SUS questions (ranging from 1 to 5, the higher the more agreement) showed significant differences: SUS1 (“would like to use this frequently”), SUS5 (“well integrated”), and SUS8 (“cumbersome to use”).</caption><thead><tr><th>SUS Scores:</th><th>Overall</th><th>SUS1</th><th>SUS5</th><th>SUS8</th></tr></thead><tbody><tr><td>Scrolling</td><td>66.35 ± 23.751</td><td>2.33 ± 1.579</td><td>3.17 ± 1.551</td><td>3.08 ± 1.863</td></tr><tr><td>Tabs</td><td>83.13 ± 19.157</td><td>3.87 ± 1.191</td><td>4.29 ± 1.042</td><td>1.71 ± 1.197</td></tr><tr><td>Menu</td><td>80.94 ± 20.494</td><td>3.83 ± 1.167</td><td>4.25 ± 1.189</td><td>1.58 ± 1.213</td></tr><tr><td>Collapsible Fieldsets</td><td>78.75 ± 15.429</td><td>3.29 ± 1.429</td><td>4.17 ± 0.917</td><td>1.75 ± 0.897</td></tr><tr><td>H-Value, p-Value</td><td>H(3)=9.544, p=0.019</td><td>H(3)=15.24, p=0.001</td><td>H(3)=10.378, p=0.015</td><td>H(3)=12.751, p=0.004</td></tr></tbody></table>

<table><caption>**Table 5.** Subjective Rankings. Scores ranging from 1 to 4, with lower scores indicating a better overview, higher difficulty, stronger preference.</caption><thead><tr><th>Ranking Scores:</th><th>Overview</th><th>Difficulty</th><th>Preference</th></tr></thead><tbody><tr><td>Scrolling</td><td>3.63 ± 0.770</td><td>2.04 ± 1.334</td><td>3.29 ± 1.042</td></tr><tr><td>Tabs</td><td>1.96 ± 0.859</td><td>2.67 ± 0.917</td><td>2.29 ± 0.955</td></tr><tr><td>Menu</td><td>2.21 ± 1.021</td><td>2.58 ± 1.100</td><td>2.17 ± 1.049</td></tr><tr><td>Collapsible Fieldsets</td><td>2.21 ± 1.021</td><td>2.71 ± 1.042</td><td>2.25 ± 1.113</td></tr><tr><td>H-Value, p-Value</td><td>H(3)=32.854, p&lt;0.001</td><td>H(3)=5.476, p=0.143</td><td>H(3)=16.031, p=0.001</td></tr></tbody></table>

<table><caption>**Table 6.** Qualitative feedback from the post-test interviews. Transcriptions were coded into positive and negative statements and counted regarding the four NDPs.</caption><thead><tr><th>Feedback:</th><th>Scrolling</th><th>Tabs</th><th>Menu</th><th>Collapsible Fieldsets</th></tr></thead><tbody><tr><th>Positive</th><td>Usability (1)</td><td>Usability (11)<br>Overview (8)</td><td>Usability (10)<br>Overview (8)</td><td>Usability (10)<br>Overview (9)</td></tr><tr><th>Negative</th><td>Lack of Usability (17)<br>Lack of Overview (7)</td><td>Lack of Usability (2)<br>Hidden UI Elements (2)</td><td>Hidden UI Elements (4)<br>Unfamiliar Design (3)</td><td>Visual Design (6)<br>Lack of Usability (3)<br>Unfamiliar Design (2)</td></tr></tbody></table>

# 5 Discussion

The four NDPs of Scrolling, Tabs, Menu, and Collapsible Fieldsets evaluated in this work differed regarding memorability, perceived usability (SUS), subjectively ranked overview, and user preference. There were no significant differences in measures of efficiency (time needed for task completion) and navigation errors.
Scrolling performed worse than all other NDPs in every measure with significant
differences. Memorability was lower in Scrolling, indicating that users remembered
the form schema less well. One possible explanation is that Scrolling required no
direct interaction with form section titles, never showed all section titles at once, and
thus provided less overview. This lack of overview is confirmed by qualitative results
and subjective rankings. Perceived usability and user preference were also significant-
ly worse for Scrolling. The other three NDPs performed equally well with regard to
most measures, the only significant pairwise difference being higher memorability of
Menu than Collapsible Fieldsets.

Results indicate that designers should not rely on Scrolling alone, but should pro-
vide an additional high-level overview of the form schema, possibly using Tabs,
Menus, or Collapsible Fieldsets. We expect the results to be generalizable from our
case study about social network profile pages to other scenarios with similar charac-
teristics: Long, form-based UIs filled on small-screen devices where tasks include
initial filling and subsequent revision of form data in a non-linear, not strictly goal-
directed manner. Examples are forms in productivity applications, mobile app set-
tings, and system preferences. Future work should investigate further scenarios and
other, not just form-based UIs. Also, the memorability of the various NDPs should be
further examined in long-term studies.

6 Conclusion

This paper set out to compare Scrolling, Tabs, Menus, and Collapsible Fieldsets
with regard to navigation in long forms on small-screen devices. A usability evalua-
tion was performed with 24 participants in a case study on social network profile
pages. Results revealed no influence of navigation design pattern on efficiency and
errors, but the following measures significantly differed: memorability, perceived
usability, subjectively ranked overview, and user preference. Scrolling performed
worst in all of these measures. The remaining three patterns worked equally well.
Qualitative results and subjective rankings provided the explanation that the more
interactive patterns (i.e., Tabs, Menus, and Collapsible Fieldsets) offer a better over-
view than Scrolling. We conclude that designers should avoid Scrolling in favor of
the other patterns when designing navigation for long, form-based UIs that users fill
and edit on small-screen devices.

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