# Uncovering Download Fraud Activities in Mobile App Markets

## TL;DR

This paper investigates download fraud in mobile app markets by deploying a honeypot app, analyzing fraudster behaviors, and identifying features to detect fake downloads, offering insights to mitigate such activities.

## Contribution

First comprehensive study on mobile app download fraud, including real-world data collection, fraud categorization, feature evaluation for detection, and stakeholder perspectives.

## Key findings

- Identified three main types of download fraud activities.
- Validated features for detecting fake downloads from billions of data points.
- Provided strategies to mitigate download fraud in app markets.

## Abstract

Download fraud is a prevalent threat in mobile App markets, where fraudsters manipulate the number of downloads of Apps via various cheating approaches. Purchased fake downloads can mislead recommendation and search algorithms and further lead to bad user experience in App markets. In this paper, we investigate download fraud problem based on a company's App Market, which is one of the most popular Android App markets. We release a honeypot App on the App Market and purchase fake downloads from fraudster agents to track fraud activities in the wild. Based on our interaction with the fraudsters, we categorize download fraud activities into three types according to their intentions: boosting front end downloads, optimizing App search ranking, and enhancing user acquisition&retention rate. For the download fraud aimed at optimizing App search ranking, we select, evaluate, and validate several features in identifying fake downloads based on billions of download data. To get a comprehensive understanding of download fraud, we further gather stances of App marketers, fraudster agencies, and market operators on download fraud. The followed analysis and suggestions shed light on the ways to mitigate download fraud in App markets and other social platforms. To the best of our knowledge, this is the first work that investigates the download fraud problem in mobile App markets.