This exploit is using human greed and little magic.
First, at remote telephone must be enabled "Install apk from unknown sources".
Second, at some Android devices more than one application, which can install apk files. For the successful execution apk file, target phone must use standart apk installer.
Third, a bit social engeneering and nothing else!
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This exploit isn't contain any viruses or "evil app". If you want to try install any bad program at remote phone, you must edit exploit. But, it's easy.

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