How to copy and install the .apk file on the target Android device
Once the upload is complete, I open Dropbox on my target Droid device. I can see the .apk file in my Public Dropbox folder.
Long-press on the .apk file you uploaded to Dropbox. When the request window appears, click "Download." The file will download to your device. Exit to your Home screen.
At the Home screen, bring up your menu and select "Settings."
Select "Applications" in the Settings menu.
Select the "Unknown sources" check box. The following warning will appear: "Your phone and personal data are more vulnerable to attack by applications from unknown sources. You agree that you are solely responsible for any damage to your phone or loss of data that may result from using these applications." Press "OK" to continue.
Once you select OK, there will be a checkmark in the box. Exit the Settings menu.
Find the file(s) you copied. In my case, I'll open Astro and navigate to the folder /mnt/sdcard/dropbox/public where the files I've downloaded should be. Remember, your path may differ depending on your Android device.
The .apk file(s) I've copied will appear in the folder.
Click the file. In Astro, you'll see two options, "Browse File" or "Open App Manager." Select "Open App Manager."
A Summary tab will open. Click the "Install" button.
The app permissions page will display. Review the permissions and click "Install."
A progress bar will indicate that the installation has begun. Once complete, click "Open" if you want to launch the application immediately or "Done" if you would like to launch the application later.
Congratulations, you've backed up an application from one Android device and side-loaded it onto another!
Donovan Colbert has over 16 years of experience in the IT Industry. He's worked in help-desk, enterprise software support, systems administration and engineering, IT management, and is a regular contributor for TechRepublic. Currently, his professional role is as a Linux support engineer for a fast-growing Linux/FOSS consultancy group. You can follow him @dcolbert on Twitter or his personal blog, located at http://donovancolbert.blogspot.com.