Custom apps for Fortnox.

AP automation, time tracking, expenses and the rest of the work Fortnox leaves to spreadsheets. Our AI engineers build the apps on your Fortnox data around 100% of your workflow, and keep them running. Typically ready to test in 1–2 weeks.

Book a demo

No developers needed. Free test version before you commit.

Invoice approvals

Synced with Fortnox

Waiting for approval

Vendor	Amount	Status
Apex Office Supply	$1,240.00	Manager
Brightline Electric	$6,410.50	Finance review
Metro Facilities	$4,980.00	Approved
Summit Freight	$1,275.00	Posted
Northwind Print	$830.25	No PO

Yes, you can get custom apps for Fortnox.

Yes. Mercovano builds custom apps on Fortnox, connected directly through Fortnox's REST API. Our AI engineers design them around how your team works, and they read and write Fortnox data such as vendors, bills, invoices.

FortnoxAccounting

Reads and writes

VendorsBillsInvoicesCustomersChart of accountsPayments

Your appsApprovals · rules · forms

Apps you can build on Fortnox.

Each one is its own app, built around your rules and connected to Fortnox, so nothing is typed twice.

Customer	Overdue	Status
Harbor Group	$18,400	Promise Fri
Lakeview Partners	$6,200	Reminder 2
Crest Media	$3,950	60+ days
Pine & Co.	$1,120	Paid

How it connects to Fortnox.

Vendor: Fortnox
Category: Accounting
Connection: Direct API, no middleman
API type: REST
Access: Your Fortnox admin turns on API access, and we give them the exact steps.
Real-time updates: Confirmed during setup.
Writing back to Fortnox: Broad. Your automations can create and update most Fortnox records.
File import fallback: Confirmed during setup.
API documentation: Fortnox developer docs ↗

From a description to a working app.

01
Describe the app you need
In your own words: how the work runs today, who approves what, and which ERP it posts to. Click through a first version and change anything.
02
We build it on your ERP
Our AI engineers build it on your ERP's data. Your admin grants access to your ERP, with exact steps from us; we do the rest.
03
Test, launch and improve
Test it free on your own data before you commit; typical apps are ready to test in 1–2 weeks. When your process changes, the app changes with it.

No developers on your side. Just someone who knows how the work gets done.

See how it works in detail →

100% your workflow

Your steps, approvals and policies, not Fortnox's defaults.

Connected to Fortnox

Approved work lands in Fortnox without anyone re-typing it.

One platform, many apps

Every app shares the same Fortnox connection, sign-in and roles. Add the next one when you need it.

Fortnox and Mercovano, answered.

Can I get custom apps for Fortnox?

What apps can I build on Fortnox?

Teams build invoice approvals, receipts and card spend, purchase requests, collections, month-end close and vendor onboarding on Fortnox, each with their own approval rules, forms and policies. If you can describe the process, we can build it.

How do the apps connect to Fortnox?

Your Fortnox admin turns on API access, and we give them the exact steps. The connection uses Fortnox's REST API.

Do I need a developer or IT team?

No. Our AI engineers build, connect, host and maintain your apps. You describe how the work runs today and test it on your own data.

How long does it take?

Typical projects are built and ready to test within 1–2 weeks of going ahead.

How is it priced?

You pay for the software you need, nothing more: no per-user pricing and no implementation fees.