Keywords

1 Introduction

1.1 Problem Description

The unlock function of smartphones has recently added a way to recognize the fingerprint of the user when unlocking a phone to protect the user’s personal privacy, unlike past functions in which a pattern or password input was the main unlocking method. In fact, most people now use fingerprints to unlock their smartphones. This unlocking method is not a problem when people can freely use their smartphone, but it can be inconvenient in situations where the user’s hands aren’t free, such as needing to use a smartphone while driving. For example, a person may need to manipulate navigation while driving or change the music on their smartphone when it’s connected `to their car. Because the driver can’t see or touch the phone while driving, someone else should use it instead. However, the driver has to unlock the phone with one hand each time the passenger needs to use it, which can be very dangerous if the driver looks at the smartphone to unlock it while driving. Also, every time someone in the passenger seat wants to use the smartphone, they will ask the driver to unlock it, and this situation may feel uncomfortable for both the driver and other users.

1.2 The Purpose of Study

Using a smartphone while driving can cause very dangerous situations. Therefore, through a case study conducted by observation, this study suggests a more convenient, comfortable, and safer smartphone unlocking method than fingerprint recognition: the “Use While Driving” feature for users who use phones when driving with a passenger. This method ensures protection of privacy, a user-friendly system, and safety support service.

2 Related Work

Several researches have been conducted regarding smartphone applications or devices to help safe driving situations. [2] devises a mobile application that gauges driving habits based on in-vehicle acceleration measurements and gives corresponding feedback to drivers. Also, [3] created the “CafeSafe” app for Android phones which has sensors on the phone to find and notice dangerous driving conditions in and outside of the vehicle. “CafeSafe” monitors the driver’s conditions or detects road situations using the car’s front and back camera by utilizing computer vision and a machine learning algorithm. [4] also suggests “TEXIVE,” a system leveraging internal sensors in regular smartphones by recognizing the micro-movements of smartphone users and detecting the driving and texting behaviors of users, which distinguishes drivers from passengers. In other words, they propose the critical task of detecting the user behavior of driving and texting at the same time. “TEXIVE” can identify dangerous operations with good sensitivity, specificity, and accuracy. According to these researches, many services and functions are continually developed to support people’s driving situations and these functions will receive attention from various fields.

3 Methodology

3.1 Data Gathering

Driving a car and using a smartphone with a passenger in the car is a situation that happens in everyday life. Therefore, this study wanted to collect data directly from natural situations through the method of observation. For this study, the subjects of this observation are people who have their own smartphone or cars. However, a person who doesn’t have a smartphone or a car can be the subject of this observation if they have experience using someone else’s smartphone.

In the first participant case, MJ usually uses smartphone to connect the Bluetooth for playing music and making phone calls. Also, he often uses navigation when going places outside of Bloomington. However, he often changes the song while driving, and if he has a passenger, he makes the passenger choose the song they want to hear. However, soon after choosing a song, the screen of the smartphone turns off and the phone is locked again. MJ needs to unlock the smartphone each time but doesn’t want to be disturbed when driving due to safety concerns. Therefore, he needs a way for his passengers to play other songs and operate other functions comfortably without unlocking the phone with his fingerprints.

Next, Elisa is the second participant. When she drives, her friends often use her smartphone. The friend can use her navigation app on her behalf or play a song they like listening to. Although they have a close relationship, she sometimes feels that she needs a way to have a certain amount of privacy from her friends. In other words, she wants others to be able to use only the apps and menus she pre-specified in a driving setting mode.

Lastly, the third participant, Elena often uses someone else’s car because she doesn’t have her own car. When she rides in someone else’s car, the driver needs to concentrate on driving, but in cases when they need to use navigation, she has experience using the driver’s smartphone. However, she feels uncomfortable asking the driver to unlock the smartphone every time she wants to search for or change a song because she feels sorry that she seems to be obstructing the driver’s driving. She wants the smartphone to have a less rigorous smartphone unlock when driving so only limited functions can be used (Fig. 1).

Fig. 1.
figure 1

The figures of participants during observation (Driver and passenger)

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3.2 Findings Based on Observations and Interviews

Observation and interviews revealed participants wanted some of the following features.

Drivers and passengers need a different unlocking method from fingerprint recognition. For example, they want an added voice-activated unlocking method. Drivers also need a way to protect private data such as photo albums, text records, and phone call history. Once the phone is unlocked, passengers need a way to find and play songs and control other functions comfortably without having to ask the driver again to unlock the phone with their fingerprint (Table 1).

Table 1. Recommended features based on user needs.
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4 Conclusion

4.1 Prototype of “Use While Driving”

The “Use While Driving” mode works by separating functions for the driver and passenger. First, the new mode will allow the drivers to unlock the phone by clicking the Voice Unlock button without having to use the fingerprint recognition method. This could help drivers safely concentrate on their driving because they will not need to look at their smartphone to use some apps. Also, it protects the driver’s privacy by only allowing others to use the apps and menus the owner pre-specified for the mode by using protected, limited use functions. The brief description of this mode is expressed as follows.

  • When a user needs to unlock the smartphone through voice, user clicks “voice unlock.”

  • When user wants to quit this mode, they click the “quit” button.

  • Specific apps can be used without owner’s authorization.

  • When the user wants to change the easy-accessapps (in the Fig. 2 case, ‘music, map, and internet’), he or she clicks the “Home” button, and the user can change the settings of these app options.

    Fig. 2.
    figure 2

    Prototype of “Use While Driving” mode

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4.2 Limitations and Recommendations for Future Research

This project sets up a situation that is common in everyday life. Since the situation of driving a car with other people happens frequently, the process of selecting the subjects to observe and the observation of the problem situations were comparatively easy. However, there is something that I feel is lacking from this project. The participant selection process lacks objectivity because they were acquaintance of myself. Therefore, my perception could have affected the observation. In other words, it was not confirmed whether the users who felt the need to allow the passengers to access their smartphone when driving the car were in a general situation. This means the sample size in this study was small, so the findings cannot be applied to the smartphone user population as a whole. Therefore, when proposing these new ideas, it will be necessary to carry out observations on a wider range of users to verify the user needs. It is also helpful to support the new idea by considering examples that can be used in general as well as other perspectives, rather than assuming new ideas are limited to specific situations. In addition, a more in-depth study of smartphone use patterns in various driving situations would provide more insight.