We can a make a signed and unsigned APK file. A signed APK file can install in your device.
For creating a signed APK file:
Right-click the project in the Package Explorer
Select Android Tools -> Export Signed Application Package.
Then specify the file location for the signed .apk.
For creating an unsigned APK file:
Right-click the project in the Package Explorer
Select Android Tools -> Export Unsigned Application Package.
Then specify the file location for the unsigned APK file.