Android differences between signed and unsigned .apk files?

android

Solution

the signed apk will contain an extra folder "META-INF", which contains three files:

- MANIFEST.MF

- CERT.SF

- CERT.RSA

Problem

How many difference between signed and unsigned .apk files in android? I know only one when i integrate in-app purchase i have unsigned .apk its gives me error `Item version is not same as...` and also we cant install unsigned .apk file in android device... is there any other Diffrences ?

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