How to force install of Android App in Development Environment?

A web search you could have done reveals that the answer to your adb question is:

adb uninstall some.package.name

Note that it's not the file.apk name you use with adb install, but rather the actual package name it ends up installed as.

The normal build process uses the android debug keystore that can be found in your android folder in your home directory (path depends on your OS).

With this debug keystore your app will be signed. This debug signature can be installed on every android device in the world as long as there isn't your app with another signature already installed.

When you say you only do code checkouts, rebuild and your signature is different, than probably your build process is broken. Your debug keystore is valid for at least a year and as long as you are on the same PC while building the generated APK should never have a different signature.

For further checking you should bring some light in your development process. What do you use? Eclipse?

If you work on different developing machines, pick one keystore from one machine and put it into your version control and use this to sign your apk with the debug signature.

adb has [-r] parameter to reinstall.

adb install -r some.apk

adb install -r -d path/to/file.apk

-r to replace -d to force downgrade