Have development version of app installed at the same time as an installation from market?

What is the best way to have a development/test version of an android app installed at the same time as the released version from market? i would like to send testers a .apk file via email they can install side by side with the currently released version available through the market. how is this possible? (it guess i could sign it with the same key so they can update the existing version, but if there is a bug in the test version they can't easily go back)

the same goes for my own device - when i want to try out the version of my app from market i always have to completely remove the development version including all my data and install it from market and set it up again.. this is pretty annoying, but i guess it's simply necessary to test my app after uploading it to the market.. 开发者_运维问答and i don't have a dedicated development device..

is there a good workflow for this?

You will have to change its package name. Something like: com.you.package.test

FWIW there is now an easy way with android's new gradle build system.

One can simply specify a different application id for debug versions: http://www.lopez-manas.com/?p=294

 buildTypes {
    debug {
        debuggable true
        applicationIdSuffix '.debug'
        versionNameSuffix '-debug'
        signingConfig signingConfigs.debug
    }