Cannot install unsigned APK file on my phone I developed an app in Eclipse, and emailed to me the .apk file. It correctly downloads to my phone, then I go in Downloads and tap it. I choose "Install" and I'm getting App not installed message.

What's the problem?

I have a Nexus 4 phone, and "Unknown sources" option is selected. I can successfully install the app through Eclipse. The .apk file was exported in Eclipse from Android tools -&gt; Export unsigned application package.
Android does not allow installing unsigned applications.
You will need to sign you APK (with a debug or release key). Don't use Android tools-&gt;Export unsigned application package, but rather the regular command to export an Android APK.

The different options available to sign you app are well described here:
http://developer.android.com/tools/publishing/app-signing.html