set. In general, more category considered, more diverse the dataset is.

-   **Author:** Author artefact indicates the developer of the app.

-   **Rating Score:** Rating Score artefact is a float number that is computed based on all the app reviewers’ ratings, which is also used by app markets to rank their hosted apps.

-   **Installs:** Installs artefact illustrates the range of possible installs the app has received. Roughly speaking, the more installs an app receives, the more popular the app is.

-   **Requires Android:** Requires Android artefact provides the range of Android OS versions that the app requires running. For example, *4.0 and up* indicates that the app can only be installed and launched at devices running Android OS with version *Ice Cream Sandwich* (i.e., 4.0 or API level 14) or above versions that are released later.

-   **Updated Date:** Updated Date artefact illustrates when the latest app version is uploaded to the market.

-   **Contact:** Contact artefact provides the email address of the authors of the app. Researchers could resort to this information to contact the app developers for recommending bug fixes or simply requesting for answering some surveys.

Security
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As revealed in our recent systematic literature review 