Worry-Tree Ltd
WorryTree: a CBT app that helps people manage worry and anxiety
- Flutter
- Dart
- NestJS
For agencies
Your development team for apps and platforms
Your clients ask for an app, a portal or a back-end, and your team is full or focused on design and marketing. We build it with you: under your name or as a named partner, with a German project lead and a fixed written estimate you can quote.
Why agencies work with us
Your client stays your client
We sign an NDA and a non-solicitation clause. We never approach your clients directly, and in white-label projects we do not appear at all.
A German project lead
One contact person in Germany who speaks your language, joins your client calls if you want and is accountable for delivery.
Estimates you can quote
A fixed written estimate per phase, so you can price the project for your client with your own margin and without surprises.
A team that scales with you
Senior developers, designers and QA engineers who have worked together for years. Add capacity for one project or as an ongoing team.
What we build for agencies
iOS and Android apps
Flutter or React Native, including back-end, push notifications and store release, from your designs or ours.
Web platforms and portals
Customer portals, booking and ordering systems, dashboards and SaaS products with Next.js and a solid API.
Headless websites
Fast, accessible websites with Sanity or another headless CMS, when your client outgrows WordPress.
Back-ends and integrations
APIs, ERP and CRM integrations, payment, authentication and data synchronisation for your front-end work.
AI features
Assistants over your client's documents, automation and computer vision, with EU hosting where required.
Maintenance and support
OS updates, monitoring and a monthly hours budget after launch, so you can offer your client a care package.
How a partner project works
- 01
Introductory call
20 minutes: how you work, which projects you see, white-label or named. NDA before any client details.
- 02
Scoping with you
You share the brief or bring us into a client workshop. We clarify open questions and technical risks.
- 03
Written estimate
A fixed estimate per phase with scope, timeline and assumptions, usually within a few working days.
- 04
Delivery in sprints
Weekly demos and test builds for you, in your tools (Jira, Slack, Teams) if you prefer. You stay in control of the client relationship.
- 05
Handover and care
Source code, documentation and accounts in your or your client's name. Maintenance if you want it.
Ways to work together
White-label
We work under your brand. Your client sees your agency, your project lead and your invoices.
Named development partner
You lead the client and design, we are introduced as your technology partner and join technical meetings.
Team extension
Developers join your team for a period, work in your repositories and follow your processes, with a monthly budget.
Commercials: fixed price per phase for clearly scoped projects, or time and material with a monthly budget for ongoing work. You invoice your client; we invoice you.
Work we have delivered
From a mental-wellbeing app for a UK company to sensor-driven platforms at an international airport: see the case studies for stack, process and results.
Questions from agencies
Will you contact our clients directly?
No. We sign an NDA and a non-solicitation clause before we see client details. Contact with your client only happens when and how you decide.
Can you work from our designs?
Yes. Most agency projects start from Figma designs by the agency. We review them early for technical feasibility, states and edge cases, so there are no surprises during development.
Who owns the source code?
You or your client, as agreed in the contract. After payment, all rights pass on; code, documentation and accounts are handed over in full.
Where is the work done?
Project management and contracts are in Hockenheim, Germany. Engineering is done by our team in Surat, India, with several hours of overlap with German working hours. Data processing follows the GDPR, with EU standard contractual clauses where needed.
How fast can you start?
An estimate usually takes a few working days. The start depends on team availability; we tell you the earliest start date with the estimate, so you can plan with your client.
Do you also take small projects?
Yes, from a single feature or an API integration to a full product. Small first projects are a good way to test how we work together.
Let's talk about a partnership
Tell us briefly about your agency and the projects you see. We reply within one working day and suggest a 20-minute call.