Purchased a subscription to NetGear Armor but not sure how to set up for use

I just purchased a subsciption to netGear Armor, however, didn't receive any instructions on how to use it.  I have the Armor App installed on my cell phone from when I had a 30 day trial free trial to Armor after purchasing my Netgear AC1750 WiFi Router.  Must I now download the Armor App to my computer and to each of the other cell phones in our house in order for all our devices to be protected?  Will Armor only protect the devices when they are being used in our home, or are we also protected when using the devices outside out home?  I wish I had more technical knowledge and didn't have to ask such basic questions.  Please feel free to share any other info that you think would be helpful for me to know.

Thank you for taking time to respond to my questions.