Android certificate (can not install app by using apk file)

Question

I developed an Android app. I then transferred the bin/myapp.apk to my android phone, and try to install it. But my phone says it can not be installed.

Someone told me it is probably because of the Android certificate in my app is wrong.

But I do not understand what is Android certificate ? Is it something defined in AndroidManifest.xml ?

Solution 1

The very first thing I would check is that you allow Unknown Sources.

Settings -> Applications -> Unknown Sources, be sure this box is checked before looking into these signage issues.

Solution 2

Android certificate refers to how your app was signed, if at all. You can create an unsigned apk, or sign it with a debug key, or a release key. If it's unsigned then you'll get an error when trying to install. Also, if you try to install a debug key-signed apk over a release key-signed apk, or visa-versa, it'll also fail. If you tell us what process you're using to build the apk then we may be able to give you more info.

Why are you transferring it to your phone like that? If you want to see the exact error you're getting, connect your phone to your computer and attempt to install using "adb install yourapp.apk".

You could also email the APK to yourself and open up the attachment to install. If you want see error messages, attach your phone to your computer and do "adb logcat", and then attempt the install.

You may want to peruse this:

Signing documentation

Comments

[Sourav Ghosh]

you can never install an unsigned apk. "All applications must be signed. The system will not install an application on an emulator or a device if it is not signed."