Shipping apps with a team of agents
September 2026
Ask an agency what it takes to ship an iPhone app with a live backend, sign-in, maps and push alerts, and you will hear the same answer: a team of five, four to six months, and a price with five zeros. Mentato shipped Coasti in ten weeks. The difference was leverage: a small team, an agent team doing the building, and a person deciding and testing every round.
Coasti on the App Store: the answer, the flag map, and community reports.
What Coasti is
Coasti is a beach app for Florida's Gulf Coast, built and run by Mentato. Open it and it tells you whether today is a beach day, and which beach: lifeguard flags, surf, tides and hazards, pulled from federal and research data and refreshed around the clock. It has sign-in, push alerts that know not to nag, and a website at coasti.app that gives the same answer on the open web. By the industry's own definitions, that is a medium-complexity app.
The standard answer
The guides agree with each other. A medium-complexity app takes four to six months. The team is five roles: someone who owns the product, an iPhone developer, a designer, a developer for the server side, and a tester. Agencies price that work between $50,000 and $150,000. It has been the answer for a long time: a 2013 survey of a hundred app designers put a first version at eighteen weeks, and nothing since has moved it much.
What it took here
Ten weeks from the first line of the prototype to the App Store, with the launch build done in four of them. One person set the direction and tested every round. An agent team did the building.
| The standard answer | Coasti | |
|---|---|---|
| Time to the App Store | Four to six months | Ten weeks |
| The launch build | Three to six months of development, then three to six weeks of testing | Four weeks, tested as it went |
| The team | Five roles | One person and an agent team |
| The cost | $50,000 to $150,000 at an agency | One person's time, plus the agents |
That is the compression. The distance from idea to execution to result went from months to weeks, the team from five roles to one person and an agent team, and the cost came down with them. AI was the lever. The person supplied the taste and the testing.
How the agent team builds
One lead agent owns the design, the product decisions and the review. It hands the work out to builder agents, each with a brief: what to change, what not to touch, and the bar to clear before reporting back. Builders never ship anything. The lead checks every change against the running app, then accepts it or sends it back. Some of the work runs overnight, inside limits written down in advance, with a summary waiting in the morning that ends with the person's to-do list.
Where the person stays in the loop
Our founder never wrote a line of the app, but set the direction, tested every round on a real phone, sent back numbered notes with screenshots, picked between options, and said no often. Decisions were written down and not reopened.
Three things on launch day could not be undone: two changes to the live database, and the upload to Apple. The agent had the access to push the build to Apple on its own, and it stopped and asked before each one anyway, even though the plan had been approved that morning. A yes earlier in the day does not cover a specific action later.
How the quality held
Before launch, a second review found 15 more problems that 452 passing tests had missed, and that review runs before every release. Since launch the same team has kept shipping, and feedback filed in the morning has gone live as a fix the same day.
The same answer on the open web at coasti.app.
What this means for your business
Most businesses do not need an iPhone app. They need the same compression on the work they already do, like intake, quoting, follow-ups and reporting: from idea to a result that is built, tested and running, in weeks, by a small team. When that distance shrinks, the next idea can start while the last one is still paying off, which is how a small team scales faster. Mentato is a small team powered by AI, and that is how we deliver big results at speed. The agent team that built Coasti is the one that builds those systems on our services page, and if the right answer for your business is an app, we build those full stack too.
Sources for the industry figures: Clutch (20 to 40 weeks for a typical mobile app; development three to six months, testing three to six weeks); the GoodFirms survey (61.6 percent of development firms average four to six months); Intellectsoft and the GoodFirms iOS cost guide ($50,000 to $150,000 for a medium-complexity app); Netguru (the five roles); the 2013 Kinvey survey (eighteen weeks). Coasti's figures come from its build records.
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Related: The build is now the cheap part