2. This method requires rooted device with busybox installed or integrated into the Android. The app is 'Titanium Backup', you could download from playstore. After install launch open and touch Backup/Restore Tab. All installed apps together with system apps will show up. Soft touch menu on you device and touch open 'Batch actions..'. Select 'backup user apps' in the backup section and wait to finish.... voilla! all user apps are backed up
NB: 1. this also backup apps data. that's for instance all whatsapp messages, audio and videos are backed up together with the apk!
2. If want to restore, follow the same steps above and select 'Restore user apps' from the resfore section....... done!