Ninox Database for Mac
Ninox for mac syncs data nicely with iCloud. You'll need just one license to install Ninox on multiple Macs and keep everything in sync. Of course, sync does also work with the iPad and iPhone app.
macOS (10.10 Yosemite, 10.11 El Capitan, 10.12 Sierra), 50 MB of free hard disk space, 4 GB RAM