Read http://arstechnica.com/security/2015/11/new-type-of-auto-rooting-android-adware-is-nearly-impossible-to-remove/
In the past you would not have an issue but today the malware and more is so rampant you would not want to go outside the Play Store.
how to download a app and installed on ****android phone without play store and which will be best forever?
****Link disabled by moderator as it's not required for the question.

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