This site
helped me a lot to properly sign the unsigned apk. But,for the last process i.e. for jarsigner
,following command need to be used
jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore my-release-key.keystore my_application.apk alias_name.
Further do look upon this unable to sign zipexception
if you encounter with any zipexception
error . So overall,use following procedure
keytool -genkey -v -keystore debug.keystore -alias android -keyalg RSA -keysize 2048 -validity 20000
jarsigner -verbose -sigalg SHA1withRSA -digestalg SHA1 -keystore my-release-key.keystore yourapkalign.apk alias_name
zipalign -v 4 yourapk.apk yourapkalign.apk
Now,you can successfully install the apk file.