App Modernisation, Managed
Your legacy app, modernised in two weeks.
We rebuild outdated iOS and Android apps on a modern framework using AI-powered code migration, preserving your branding and features, and then manage App Store compliance, security and OS updates for you, on a monthly subscription.
No agency brief. No four-month timeline. No surprise quote. Just a working, modern app, and a service that keeps it that way.
Two-week delivery · Made in the UK · Ongoing managed service

If your app is two years behind, it is already costing you customers.
The app still works, just about. But it looks dated, the sign-up flow does not meet modern standards, the build tools carry security vulnerabilities, and every iOS or Android update brings another round of urgent, expensive fixes.
Most businesses do the minimum to stay listed. Ratings slip. Users drift away. The gap between your app and your competitors widens.
We close that gap in two weeks.
Multizone is a managed service built specifically for this problem. We take what works, rebuild what does not, and add what is missing, using AI-powered migration so we move at a speed and price that no traditional agency can match.
After delivery, our monthly subscription handles compliance, security, OS releases and device support. You stop worrying about your app.
What you get
Everything below is included in the two-week delivery. Ongoing management is a separate monthly subscription.
Modernised iOS and Android app
Phone and tablet form factors, current OS targets, modern navigation, modern sign-up flows.
Your branding preserved
We keep what makes the app yours. Visual identity and core features carry through.
Security audit and fixes
Outdated dependencies and known vulnerabilities resolved before the app ships.
App Store and Google Play submission
We handle store submission and review. We have a 100% approval track record.
Ongoing managed service
Monthly subscription covers OS updates, device support, store policy changes and security patches.
One point of contact
No developer management. You speak to Angus. We handle the rest.
How it works
Four steps. Two weeks. One subscription that keeps you current after that.
1
Audit
An AI audit of your existing app: what to preserve, what to rebuild, what is missing.
2
Migrate
Our AI migration engine rebuilds your app on a modern framework. Two weeks.
3
Deliver
You review and approve. We submit to the App Store and Google Play.
4
Manage
Subscription begins. Compliance, security, OS releases, all handled.
A managed service, not an agency.
Agencies are set up for bespoke builds: long timelines, ballooning scope, unpredictable cost. That model is part of the problem you are trying to solve.
Multizone is built for one thing: taking a legacy mobile app and bringing it back to current standards, fast, then keeping it there. That is why we can quote a fixed two-week timeline, a fixed delivery fee, and a flat monthly management price.
Why we created fixed price mobile app modernisation services ›
Multizone vs. the alternatives
| Agency rebuild | DIY app builder | Multizone | |
|---|---|---|---|
| Timeline | 3–6 months | DIY | 2 weeks |
| Cost predictability | Variable | Fixed | Fixed |
| Migrates from existing app | Yes | No | Yes |
| Ongoing management | Reactive billable hours | None | Subscription |
| Resource you provide | Project manager + brief | Developers + time | A 20-minute call |
The four Multizone services
Advanced App and Sophisticated App are fixed-price modernisation services, which is what most visitors come here for. MVP App and App Platform are day-rate consulting, for earlier or more strategic points in an app's life.
Day rate
MVP App
You have an idea but no app yet. We help you build the smallest version that proves it.
Read more ›Fixed price
Advanced App
Modernise your existing app at a fixed price, in two weeks. Then keep it healthy under our Maintain subscription.
Read more ›Fixed price
Sophisticated App
Modernisation plus deeper design and feature work, in three weeks. Then keep moving forward with our Enhance subscription.
Read more ›Day rate / retainer
App Platform
Your app is now business-critical. Senior product and engineering oversight at fractional CTO level.
Read more ›Pricing, in plain English.
Apps decay if you ignore them. New phones, new operating systems, new store policies. The two-tier offer below pairs a one-off modernisation with a subscription that keeps the decline at bay.
- Advanced App: from £4,995 + £495 / month (Maintain)
- Sophisticated App: from £7,995 + £995 / month (Enhance)
- Audit: free, no commitment, 24-hour turnaround
Subscriptions begin once your modernised app ships. Twelve-month minimum term. Annual prepayment unlocks subscription discounts; thirty-six-month commitments waive the modernisation fee entirely.
See full pricing ›Free
Get the audit first.
Send us your App Store and Google Play links. We will tell you, inside 24 hours, what your app needs and what it would cost. No commitment to proceed.
Request the auditCommon questions
More on the full FAQ.