Keywords

1 Introduction

The number of mobile applications available has grown dramatically in the last few years, and the app stores are indeed the main channel for dissemination of such applications [2]. The number of mobile apps available in leading app stores reached the 5.7 billion by the end of 2016Footnote 1. By 2017, the number of app downloads is estimated to increase up to 268 billionFootnote 2. The penetration factor that allows reaching customers with apps is extremely high as there is a large customer base owning smart-phones whereas, at the same time, there is a huge competition in this market.

Mobile application developers and companies usually rely on app-relatedFootnote 3 success factors, the majority of which are directly related to their economical/business profit (e.g., number of downloads, or in-app purchases revenue). However these success factors are limited by how well the application fits user’s needs or how well satisfies the user’s expectations (among many others). Based on empirical evidence [4]: some studies suggest relations between API quality and app success [3, 9], whereas the study by Guerrouj and Baysal [4] showed that even more significant factors were app-size and category. Similarly, Corral and Fronza [1] found that source code quality only had marginal impact on app success (measured as penetration and satisfaction), while the most important quality attributes were “responsiveness, easiness, functionality and performance”. Several studies used data mining to understand the information in app-stores [8, 10], e.g. to find issues in applications and thus ways to improve them [8].

App stores include certain user-visible information (e.g., such as description of the app, screenshots, application size, last update, rating, and permission requirements). Some of these information items are under control of the app developers (e.g., the app description, the screenshoots, or the permission requirements), whereas some others are the direct expression of the users opinions (e.g., reviews and rating). These reviews and ratings have become an important factor for app success [6] and its impact has been analyzed in several studies (e.g., [5, 7]). However user ratings might also be helpful for developers and application vendors to identify and prioritize missing features [11]. Developers can also improve the information on the app stores aiming at increasing the number of downloads of their apps. In this scenario, it is important to gain understanding on the criteria that make users to choose, download and install mobile apps, but at the same time, it is also important to analyze the rationale behind users removing mobile apps once it has been already installed in their mobile phone.

In this paper, we study the mobile application quality from the user perspective through an online survey. We analyze the set of reasons (i.e., user-related factors (see Footnote 3) that might influence the users while choosing to install mobile applications via app stores and the reasons that cause them to uninstall an app from their smartphones.

2 Survey Definition

Research questions: The two main research questions addressed in this work are:

  • RQ1: What are the user-visible information items from the app stores that are taken into account by users when choosing, downloading and installing applications?

  • RQ2: What are the main reasons for deleting an application?

Target population: The survey was executed at the end of 2015 and it includes results obtained from 121 users, some of which were contacted through mobile apps forums such as IPhone Forum, EverythingiCafe, Android forum, and AndroidPit. Hence, a convenience sampling approach was used.

Questionnaire design: The survey questionnaire comprised the following aspects: (i) Demographics (categories of questions: gender, age, occupation, years of experience using smartphones, nationality, and country of residence); (ii) application and network usage (e.g. cellular data plan); (iii) reasons for installing and deleting applications; (iv) important characteristics of mobile applications,; and (v) qualitative feedback on mobile application and smartphone experience.

Data analysis: Descriptive statistics and histograms are used to illustrate the distribution of the data. In addition, we applied pair-wise Fisher’s exact test to analyze the differences between the reasons to download or uninstall apps, although the main goal of the study was not to generalize the results for the population based on the results of these tests.

Validity threats: The main threats to validity are: (i) use of convenience sampling, sample size and inclusion of personal contacts, which might limit the ability to generalize the results to a large population; (ii) objectivity in the coding of the open questions, which may introduce bias; (iii) the inclusion of participants from mobile applications forums, which might have also influenced the results.

3 Results

Demographics: The demographics of the subjects that participated in the online survey is given in Fig. 1, including age, gender, smartphone experience, phone type, as well as user nationality and occupation.

Fig. 1.
figure 1

User demographics and Mobile platforms.

Full size image

The subjects were from 26 different nationalities, although the majority of them are Turkish (\(25\%\)) and Swedish (\(21\%\)) citizens. The participants’ occupations spanned through 23 different occupations, with a vast majority of students (\(57\%\)), engineers (\(17\%\)), or researchers (\(11\%\)).

Reasons for installing new apps from the App Store: The participants were asked to prioritize the relative importance of a set of reasons they have into account when deciding to download certain mobile applications via app stores. Figure 2 shows a summary of the participants responses. We have found statistically significant differences (\(p<0.005\)) when participants’ responses in relation description of tool and user reviews are both compared to the remaining seven reasons. Key observations are: (i) user reviews are significantly more important than application size, content rating, editor’s choice, last update, number of downloads, permission requirements, and screenshots; (ii) no significant differences were found between number of reviews and review content, and (iii) no statistically significant differences were found between rating values, frequency of ratings and number of ratings, which indeed goes in the same direction than previous studies (e.g., [7]).

Fig. 2.
figure 2

Reasons from users to install apps.

Full size image

In addition, the users have provided additional items that they think are important, resulting in the following list: open source, graphics, e.g. videos/screenshots, source company programmer reputation, bad naming of apps for advertising such as “Free version”, social popularity (e.g. if a friend is using and recommending it), compatibility with other apps, needs, position in the list, or existence of an external app website.

Reasons for deleting apps: We coded the different reasons for deleting apps, and categorized them in 16 categories. The main reasons for users to uninstall applications from their smartphones is given in Fig. 3.

  • Unstable/Inconsistent: Involuntary behavior, uncontrolled actions, Inconsistency between description and functionality, unreliable, change in privacy terms, side effects (i.e. together with the main purpose, it does extra unwanted things), permissions, high amount of notifications, expectations not met.

  • Intrusive Advertisements

  • Lack of Improvement: outdated, lack of Improvement/others outperform, finding a better one

  • Useless/Not needed: Usefulness, not using anymore, not needed

  • Frequent application updates: Frequent application updates, fee for upgrade, too many updates

  • Getting bored: e.g. Finished game

  • High memory allocation: Size of the app, too much memory usage (RAM), uninstallations by relying on the backup to use it later

  • Poor User Interface: Slick animations, complex to use, GUI, user unfriendly

  • High battery usage

  • Crashes: Performance, Sluggish behavior, freeze, slow, laggy, force quit

  • Time consuming: Addiction, abuse

  • No offiline use: No offline use, no caching

  • Poor Popularity: friends not using, overall reputation

  • Abusing privacy: login required, required integration via login (i.e. with Facebook, Google)

  • Compatibility with device version

  • OS/ROM change

The most important reason was due to the fact that they find that the app has become useless or is not needed any more.

Fig. 3.
figure 3

Reasons from users to uninstall apps.

Full size image

4 Conclusion

In this paper we have presented the results obtained via user surveys focusing on the user-related success that might lead users to choose and install certain apps, as well as user-related failure factors, that might lead users to uninstall the apps. The description of the tool and user reviews are the most important factors influencing users while choosing and installing application from app stores. The most important reason for a user to uninstall an application from smartphone is users finding some apps as “useless”. The other important factors found as relevant are crashes, high memory allocation, instability and inconsistency, poor UI, intrusive advertisements, lack of improvement, boring apps. We are aware that this study only provide preliminary results on the user-related success and failure factors, and that further surveys and user studies need to be conducted, in particular expanding the target groups and covering different locations.