1. Meaning of signature

In order to ensure the legal ID of each application developer and prevent some openers from confusing and replacing the installed programs with the same package name, we need to uniquely sign the APK files we publish to ensure the consistency of the versions we publish each time (for example, automatic updates will not be impossible to install because of inconsistent versions).

Step 2: Sign.

A. create a key

B. use the key generated in step a to sign the apk.

3. Specific operation, signature apk under the command line (principle)

You need Keytool.exe (located in jdk 1.6.0_24\jre\bin directory) to create the key, and use jarsigner.exe (located in jdk 1.6.0_24\bin directory) to sign the apk. After adding the directories where the last two softwares are located to the environment variable path, open the cmd input.

d:\ & gt； keytool-genkey-alias demo . keyalg RSA-validity 40000-keystore demo.keystore/* Description: -genkey generates key-alias demo. keystore alias demo. keystore-KeyalG RSA uses RSA algorithm to encrypt signature -validity 40000 is valid for 4000 days-keystore demo. keystore */d: \ > Jarsigner -verbose -keystore demo. keystore -signed jar demo _ signed.apkdemo.apk demo.keystore/* description:-verbose output signature details-keystoredemo.keystore location-signed jardemo _ signed. Apkdemo.apkdemo. keystore is officially signed, and the three parameters are file demo _ signed, and then file demo. The apk to be signed and the keystore demo.keystore.*/

Note: demo.apk in the bin directory of android project has been signed by debug user by default, so you can't use the above steps to sign the file again. The correct step should be: right-click the item-> The apk exported by anroid tools-export unsigned application package is signed by the above steps.