Use download to describe the intentional transfer of data and files to a system or device. Use install to describe adding apps, hardware, and drivers to a device.
When you use download as a verb, describe what the customer is transferring and where the customer is transferring it to.
Don't use download to describe the process of opening, viewing, or switching to a webpage.
It's OK to use download as a noun to describe data or a file that's available for downloading or that has been downloaded.
In your writing, make sure it's clear whether download is used as a noun or verb.
Examples
Install the app.
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