未签名的Android APK文件将无法安装

Question

I created an unsigned APK file from my eclipse project to demo my app on another device. It runs fine on the emulator and on a connected phone. When I emailed it and downloaded the apk file ( I have allow apps from unknown locations ticked on ) but the install fails with message. "Installation failed" and not much more info. Any ideas what I can check?

Answer 1

Make sure that the os version of phone on which you trying to install the app is meet the minSdkVersion that you declared in your manifest file. Or if that app is already installed then unistall that and install again. May be it works.

Answer 2

I had the same problem. It was solved by uninstalling the version I had installed via usb from Eclipse. Once that version was off my phone I could email myself APK's and they would load fine.

Answer 3

All your apps need to be signed. Read here:

http://developer.android.com/tools/publishing/app-signing.html

Sign it with something like jarsigner

Answer 4

On the device, go to Settings->Applications->Unknown Sources and make sure that is ticked.

Make sure that there is enough space on the phone, and that the phone is running on the right version of Android.

Finally, if this still doesn't work, then sign your .apk file.

Answer 5

I had the same problem and in the end just signed apks which let them install perfectly. Alternatively if you use something like astro of the play store to backup your apk from the phone running it and send it over to the other phone - this also works. I think it might not be packed right or for some reason it requires a signature to install. It could also be that conflicting signatures are found on the new phone.