After loosing one of our main applications to corruption, I implemented RSM (Repository Snapshot Manager). This is much more than backing up the applications. It backups all you configuration settings, certificates, logs, scripts, etc. It can be used to restore your environment after a complete loss or you can restore one application or file if need be. It's very easy to configure and use. I currently keep a rolling 5 day backup just for safe keeping. You can find it in Qlik Help.
As for application migration, I am assuming that you have two separate installations of Qlik. One development and one test. There is a tool on GitHub that may be useful. I have not installed nor used it but it looks promising. I believe that it allows for you to export from one installation and import to another installation. This may be what you are looking for.
GitHub - eapowertools/QlikSenseQMCUtility: A collection of management console utilities for use with...
If you installation is a multi node installation. This can be accomplished using Sync Rules.
Hope this helps.