Shortly before the Fire Phone was made official, Amazon announced that its Appstore had amassed over 240,000 apps and games. An impressive number, no doubt. Yet when you fire up your new phone the first time and start searching the Appstore, you're bound to be disappointed by the lack of key apps.
For those who find the lack of apps maddening, rest assured knowing there is a solution: sideloading. I know, "sideload" is a weird term. Fret not, my friend. In essence, it means installing (loading) an app outside of the preferred method of the preinstalled Appstore.
You'll need to change one setting before you're able to sideload an app. Launch the Settings app on your Fire Phone, then tap on the "Applications & Parental Controls" listing. In the submenu that displays, find and select "Allow non-Amazon app installation." By sliding the switch next to the first listing on the next page, you'll allow apps to be installed from secondary sources. Once you enable this option, you'll receive a stern warning about putting your personal data at risk due to sideloading. If you're comfortable with taking responsibility for what you load on your device, tap OK.
As for finding Android apps (commonly referred to as an APK), well that part is a little tricky. For those with enough Google fu, it won't take too long to figure out you can use a Chrome extension to download the APK for free apps directly to your desktop. From there, transfer the file over to your Fire Phone using Dropbox or the like and install the app by opening the APK file. FireOS will recognize the APK as an app and begin the installation process.
There's a pretty big caveat to sideloading apps on the Fire Phone. Since Amazon heavily customized Android to fit its own needs, thus leaving out all Google services, some apps just won't work. Starbucks and Foursquare both require Google Play Services, and thus don't run on FireOS. Naturally, all Google apps (Gmail, Google Drive, Google+, and so on) won't run. Despite the extra effort required to sideload an app, it's well worth the time.