Google Play only wants to install directly on your device. Which makes it tough to side-load if you don’t have WIFI.
I loved CYRKET
Which was taken down.
Let’s say you’re in the impossible situation of having cancelled your smartphone’s contract, kept the “phone”, and had the wifi-radio die. After thinking it was a software issue you wiped the whole thing back to factory-metal, and only then discovered that it was indeed a bad radio. How do you install anything?
If you’re like me, you’ll let the phone sit around for a year gathering dust, then google like mad the night before a vacation and discover Installing an Android App from the SD card without a File browser.
The long and the short of it -- type
file:///path/to/file.apk into the browser. It wouldn’t hurt to rename the
.apx to something reasonably easy to type.
http://matthewturland.com/2012/03/15/sideloading-google-play-apps-onto-a-kindle-fire/ - an edge-case that doesn’t apply to my situation, but interesting.