A few days ago, Google removed popular Cheetah Mobile and Kika Tech apps from its Play Store following a BuzzFeed investigation<\/a>, which discovered the apps were engaging in ad fraud. Today, as a result of Google\u2019s ongoing investigation into the situation, it has discovered three malicious ad network SDKs that were being used to conduct ad fraud in these apps. The company is now emailing developers who have these SDKs installed in their apps and demanding their removal. Otherwise, the developers\u2019 apps will be pulled from Google Play, as well.<\/p>\n To be clear, the developers with the SDKs (software development kits) installed aren\u2019t necessarily aware of the SDKs\u2019 malicious nature. In fact, most are likely not, Google says.<\/p>\n Google shared this news in a blog post today<\/a>, but it didn\u2019t name the SDKs that were involved in the ad fraud scheme.<\/p>\n TechCrunch has learned the ad network SDKs in question are AltaMob, BatMobi and YeahMobi.<\/p>\n Google didn\u2019t share the scale to which these SDKs are being used in Android apps, but based on Google\u2019s blog post, it appears to be taking this situation seriously \u2014 which points to the potential scale of this abuse.<\/p>\n \u201cIf an app violates our Google Play Developer policies, we take action,\u201d wrote Dave Kleidermacher, VP, Head of Security & Privacy, Android & Play, in the post. \u201cThat\u2019s why we began our own independent investigation after we received reports of apps on Google Play accused of conducting app install attribution abuse by falsely claiming credit for newly installed apps to collect the download bounty from that app\u2019s developer,\u201d he said.<\/p>\n The developers will have a short grace period to remove the SDKs from their apps.<\/p>\n The original BuzzFeed report found that eight apps<\/a> with a total of 2 billion downloads from Cheetah Mobile and Kika Tech had been exploiting user permissions as part of an ad fraud scheme, according to research from app analytics and research firm Kochava, which was shared with BuzzFeed.<\/p>\n Following the report, Cheetah Mobile apps Battery Doctor and CM Launcher were removed by Cheetah itself. The company additionally issued a press release<\/a> aimed at reassuring investors that the removal of CM File Manager wouldn\u2019t impact its revenue. It also said it was in discussions with Google to resolve the issues.<\/p>\n As of today, Google\u2019s investigation into these apps is not fully resolved.<\/p>\n