The way I look it this issue is this.
My ability to write this response to you in this forum is totally dependent on the freely-given efforts of thousands of people over decades. Whether it’s the Chromium browser I’m using, the WWW in the first place, the Debian Linux system it’s on, the GCC compiler that built it all, the very concept of TCP/IP networking, or any of the other zillions of open-source projects underpinning all of that, I didn’t have to directly pay anybody for it. This, naturally, is also totally true of Ionic Framework, and all the stuff underneath it.
I have donated money and contributed to some of these projects over the years. I have had people pay me to develop software that is itself based on these free projects. I try to be responsive to my customers’ needs, and like to fantasize that I’m good enough at doing that to make a living. I would rather concentrate my effort in that direction - making more and cooler apps, or helping other people to turn their visions into reality - than towards the “walled guarden” (deliberate misspelling) model of obfuscation and copy protection. I feel I am a happier, if not monetarily richer, developer and netizen with this worldview.
All that being said, if you’re still reading, I don’t know what your app domain is, so I’ll just have to generalize, but many mobile apps involve production, consumption, and transmission of information. If your app domain can somehow involve information that you generate or curate, then that would seem to be a logical place to move it to the server. Offline or unapproved clones would have stale data, providing an incentive to use your official app. Some other app domains lend themselves to community building, which is another place you can differentiate yourself from somebody peddling a clone of your code. Finally, you can sell support or do “feature bounties”.
In summary, we’re all standing on the shoulders of free software giants here, so I think it feels most natural to adopt their strategies for finding ways to get compensated for their effort, instead of trying to retrofit economic models built on scarcity of physical objects.