I recently discovered a new file on my phone, named .appodeal, at the base of the Internal shared storage folder.

It appears to be a text file with just 4 characters: e30=.

How can I tell what app left it there, and what nefarious/tracking purpose it has?

The phone's currently running Android version 7.1.2.

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    I have file too on 3 phones (marshmallow 6.0, jb 4.2 and 4.1.2) all have same content "e30=" I never payed attention at it. I guess it's some Android stuff or from some app (but can't be tracked back since internal/external storage is world r/w), but I can't find any info about it on Google or I'm too stupid? – Једноруки Крстивоје Aug 4 '17 at 23:55

It seems to be from an ad revenue targetted app by the same name appodeal on the play store and Google search reveals multiple references

Try to track it in your phone using Anti adware or use ad blockers from Izzy's list

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    +1 on yours too, for putting forward a supposedly easier solution to track the app down. – Andy Yan Aug 5 '17 at 1:23
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    By the way, e30= is Base64 for {}. – Grimoire Aug 5 '17 at 14:02
  • @DeathMaskSalesman: Thanks and what would be the significance of it? – beeshyams Aug 5 '17 at 14:06
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    @beeshyams Disembodied from its context, it's almost impossible to identify the meaning of a curly brace. Without the code to look at, I can't tell. – Grimoire Aug 5 '17 at 14:09
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    @beeshyams The content of my comments is not worthy of an answer per se. If you read them again, you'll see that I did not say anything dramatically different from your and Andy's answers. – Grimoire Aug 5 '17 at 14:49

This is generated by the Appodeal advertisement SDK integrated in some of your installed apps, likely to act as some sort of flag.

As for telling which app generated it, aside from going the hard way (installing and starting the apps one-by-one), you should also be able to use tools like MyAndroidTools to check the services and broadcast receivers an app possesses. Apps with ad SDKs will likely have services and receivers dedicated to maintaining the SDK.


Thanks to previous posters. In my case it seems to be the RainToday app as the file is regenerated each time I run the app. Fair enough as the app is free if you put up with ads.

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