Install your own software Possible Duplicate:
  How can I install an app given only its APK file?  




I'm thinking abount getting a smartphone, mainly for tinkering with it. On iOS, in order to install your own code, you need to either root the device, or buy into Apple's developer program. What's the current state of things in the Android world? I see the SDK and developer documentation are readily available, but people talk about Kindle's Fire and Google's Nexus as closed systems.
You can give someone the APK generated when you debug your code, and they can insall it provided that they activate the flag "install from untrusted sources" (or something like that... don't know the exact words because I have the italian localization)

BTW: distribution of APK signed with the SDK-generated debug certificate is a bad thing, you have to sign it with your own key