REI3 replaces 6 paid apps
One open-source tool, 6 subscriptions it can stand in for. Each pairing below is curated and verified by hand, with the honest catch spelled out. No votes, no pay-to-list.
LicenceMIT
Plateformesyour server
InstallationNative Linux/Windows server package or Docker Compose, connected to PostgreSQL
DonnéesHuman-readable application records and configuration live in a PostgreSQL database controlled by the operator
ConfigurationYou must provision PostgreSQL and configure a server/reverse proxy; it is not a managed one-click workspace
facts verified 2026-08-10
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
the catchIt lacks Caspio's turnkey hosted deployment and embedded public-app workflow, leaving server operation and external publishing to the user.
the verdict →all Caspio alternatives →
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
the catchREI3's utilitarian forms, reports, and pages are a poor substitute for Bubble's highly customized public front ends and interaction design.
the verdict →all Bubble alternatives →
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
the catchIts utilitarian self-hosted business interfaces are less polished for branded external portals and nontechnical customer access than Knack.
the verdict →all Knack alternatives →
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
the catchREI3 has far fewer ready-made integrations and less mature enterprise governance than Quickbase, so more of the surrounding workflow must be built and operated manually.
the verdict →all Quickbase alternatives →
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
the catchREI3 can build functional role-aware apps, but its visual design, templates, and external portal experience are much more utilitarian than Softr.
the verdict →all Softr alternatives →
A sober business-app builder with forms, reports, roles, workflows, and no per-user meter.
the catchIt produces capable browser-based business apps but not AppSheet's native-feeling mobile client, offline behavior, and spreadsheet expression model.
the verdict →all AppSheet alternatives →last updated 2026-08-10 · up to $5,856/yr replaced · no votes, no pay-to-list
