Joist comparison
Joist is an estimating and invoicing app. WOPA invoices from WhatsApp.
Joist is the better fit if estimates and a dedicated contractor app are central to how you work. WOPA is for the fastest path from a chat message to a sent, chased invoice.
Compare
Different jobs, different tools.
| Need | WOPA | Joist |
|---|---|---|
| Invoice from WhatsApp | Core workflow. | Invoicing happens inside the Joist app, not chat. |
| Payment reminders | Chat-first reminder workflow. | Available within the app. |
| Estimates and quotes | Not the focus. | Strong fit. |
| UK invoices, VAT and CIS | Built for the UK. | Check current UK and VAT support. |
| Best fit | UK trades who want fast invoicing from chat. | Contractors who want estimates and invoices in one app. |
Both create invoices. The difference is where the work starts: a dedicated estimating app, or a WhatsApp message.