APK tools side note and how to sign a releaseed APK.

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####     How to unpack APK?    ####
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1. Put apktool, apktool.jar under the same folder.
2. Run "apktool d xxx.apk".

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####     How to pack files into APK?    ####
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1. Put apktool, aapt under the same folder.
2. Run "apktool b xxxx-folder-name".
3. The output will be under xxxx-folder-name/dist/ with name xxxx-folder-name.apk.

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####    How to create keystore?    ####
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Refer to http://developer.android.com/tools/publishing/app-signing.html
 1. Run "keytool -genkey -v -keystore steven.keystore -alias steven -keyalg RSA -keysize 2048 -validity 10000"
 2. Verity keystore with "keytool -list -v -keystore ./steven.keystore"

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####    How to sign an APK?    ####
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Refer to http://developer.android.com/tools/publishing/app-signing.html
1. Run "jarsigner -verbose -keystore  ./steven.keystore -signedjar xxxx-signed.apk xxxx.apk steven"
   or  "jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore steven.keystore ./xxxx.apk"
2. Verify the signed APK with "jarsigner -verify -verbose ./xxxx.apk"

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####    How to laing an APK?   ####
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Refer to http://developer.android.com/tools/publishing/app-signing.html
1. Run "zipalign -v 4 xxx-unaligned.apk xxx.apk"

zipalign ensures that all uncompressed data starts with a particular byte alignment
relative to the start of the file, which reduces the amount of RAM consumed by an app.