On-Demand VPN Android Options

I use the Wireguard VPN app on my iPhone to connect to my FWP when I'm not home. It has an integrated on-demand feature that I absolutely love, and I love that Firewalls supports Wireguard so I can take advantage of this. Kudos to the team for supporting this. What I've realized is that the Android app doesn't support on-demand. I know this isn't a Firewalla issue, but I'm curious if others have come up with a solution for this. My kids have Android devices, and I'd love to filter them through our FWP when they leave the house, without them having to toggle the VPN on and off. The chances of that happening are pretty low. I love that I can let the kids use their tablets without a ton of supervision at home because of the Firewalla. I trust it to do what I've configured it to do. I want to have that same sense of security when they leave our home, so I'm curious how other people have solved this problem. I've thought about just setting it up so they're always on the VPN, even at home, but I feel like that isn't really a good long term solution. I've tried using Android's Automate app as well, but the free version is pretty limited, to 30 minutes of automation if I remember correctly. I like with Firewalla there are no monthly fees. As ironic as it sounds, we love that so much we're looking at buying more of these devices to support what the company is doing, and gifting them to others. (I hate monthly fees but I don't mind one-time up front costs for a good product like Firewalla.)

On a side note, I think ultimately I'd love to see Firewalla have both an iOS and Android app that helps us manage this, so we don't have to rely on 3rd party solutions. Perhaps it could be integrated into the existing app somehow?