Off-the-shelf integrations (Zapier, native connectors) are genuinely fine — until specific signs appear
Most businesses don't need a custom API. The question is whether specific, checkable signs of outgrowing existing connectors have actually appeared.
The signs that actually matter
- Your business logic can't be expressed as a simple trigger-action rule
- You need to combine/transform data from multiple sources before it's useful
- An off-the-shelf connector doesn't support a field or action you actually need
- You're building a product (mobile app, portal) that needs its own backend regardless
What a custom API actually solves
Business logic that off-the-shelf tools can't express, and a stable foundation for anything you build on top of it — see API & Backend Development.
When NOT to build one yet
If existing integrations (n8n, Make, native connectors — see Integrations) genuinely cover your current need, a custom API adds cost without solving a real problem yet.
Questions
Is a custom API always more capable?+
Yes, but capability isn't free — it's only worth the cost once off-the-shelf tools genuinely can't express your logic.
Can we start with off-the-shelf and add a custom API later?+
Yes — this is a common, sensible path once specific limitations actually appear.
Does building a mobile app require a custom API regardless?+
Usually yes — a mobile app typically needs its own backend/API foundation regardless of integration needs.