firstly open settings in amazon fire phone and select option
"Applications and Parental Controls" like this
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now select option " Allow Non Amazon app installation " like this
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now turn on "App Installation " option on top of options like this
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now click OK to allow your amazon phone to install non amazon apps.
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now go back to your home menu of your phone and open silk browser like this
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open URL
www.sideloadfirephone.com
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now open whatsapp from menu tab like this
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now scroll down and open a link to download APK file of whatsapp.
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after clicking a new tab will open
now scroll down to click on blue button to download whatsapp APK file like this
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now you can see your downloading file like this
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now open your storage of mobile phone and check your downloaded whatsapp file like this
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now open your downloaded file to install like this
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when you click to open the file, it will ask you to download it. click on next option like this
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you can see your installation under progress like this
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when whatsapp application install, click on option " open " like this
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now whatsapp application is install.
open your whatsapp application and it will ask you to click on the option " agree and continue" like this
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now choose your country and enter your mobile number like this and whatsapp will be install....
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thankyou.....