Apps that keep working after we leave.
Sumo Solutions is a small engineering firm focused on mobile. We build iOS and Android apps — including the AI features inside them — along with the websites and backends behind them, for founders, creators, and local businesses.
Services
Mobile app development
We design, build, and ship your app to the App Store and Play Store — then keep it working as iOS and Android change underneath it. Sign-in, payments, notifications, and the backend that feeds the app are part of the same job, not a separate project.
- iOS and Android
- App Store and Play Store release
- Backend, sign-in, and payments
- Ongoing maintenance
AI-enabled mobile apps
The AI features worth building are the specific ones: an assistant that answers from your own content, search that understands a question, transcription and summaries that save real time. We build these into the app on top of existing models rather than training our own, which keeps cost and timelines predictable — and we will tell you when a feature does not need AI at all.
- In-app assistants and chat
- Search over your own content
- Transcription and summaries
- Recommendations
Custom software & websites
Websites, web applications, and the internal tools a business runs on — including the marketing site and admin panel that usually sit behind an app. Built to be handed over, with the code documented for whoever picks it up next.
- Websites and landing pages
- Web applications
- APIs and backends
- Admin and internal tools
Mobile app security research
Independent review of Android applications, followed by coordinated disclosure to the vendor. This line is self-directed rather than client-commissioned, though we take a small number of paid reviews for teams that own the app.
- Android apps on Google Play
- Reported privately to the owner
- Never published unfixed
- Paid reviews on request
Also part of the work. Cloud hosting, deployment, and a view on what to build first come with these engagements rather than as separate products. If you need only one of those — an architecture review, or help with infrastructure you already run — write to us and we will tell you honestly whether we are the right fit.
Who we work with
Most of our work is for people who need an app built — not for companies that already have an engineering team.
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Founders and early-stage teams
Getting a first version in front of real users without over-building it. Part of our job is telling you what you can cut from version one.
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Creators and influencers
Apps for an audience you already have — membership, community, content, and subscriptions, published on both stores under your own name.
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Local and small businesses
Booking, ordering, and customer apps for a business that already works in person and needs to work on a phone.
How we work
We are a small team, and you deal directly with the people doing the building — there is no account manager in between. Engagements are small-batch by design: we take on work where we can stay accountable from the first sketch to the day it goes live.
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You own everything
The code, the accounts, and the store listings are yours. When the work is finished you can take it to any developer.
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Plain language, always
You will know what is being built and why, without needing a technical background to follow it. Ask for the detail and you will get that too.
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It has to keep working
Apps break when iOS and Android change underneath them. We build with that in mind, and we are clear up front about what upkeep involves.
- First response
- Within two business days, to either address.
- Scoping
- Every engagement is scoped in writing before work starts, under a separate written agreement.
- Capacity
- We run a small number of engagements at a time, and will say so plainly if we have none free.
- Security research
- Self-directed and independent — not operated on behalf of, or in affiliation with, any bug bounty platform.
- Reporting an issue to us
- Responsible disclosure policy, and security.txt per RFC 9116.
Contact
New projects and general inquiries
contact@sumosols.comApp projects, websites, scoping questions, and anything about the first three service lines. A sentence about what you want built is enough to start.
Security research
research@sumosols.comDisclosure correspondence, paid application reviews, and security issues in our own systems. Include the app name and package identifier where you can.
Received a disclosure email from research@sumosols.com and want to check it is really us? Reply to that address directly, and see how our disclosure process works.