You have to change the following:
- AndroidManifest.xml, change the package name: package=”com.a.b”
- apktool.yml, change apkFileName. It should be same as package name
- The main class, which will be the smali directory with a name similiar to the package name..
- Find a line:smali/../…/…/…/mainclassname.smali:1:.class public com/a/b;