The best app builder for startups is the one that still works on the day you leave it.
The best app builder for startups is the one whose output you can still use after you stop paying for it. That reads like a technicality until the week a round closes, a first engineer joins, and somebody asks to see the repository. Three of the biggest tools answer that question in writing, on their own documentation, and the answers are not the same. Everything below comes from those pages, opened today, plus Apple's own rules about who may install a build before it reaches the store. If you are earlier than that, start with validating the idea first.
What the choice depends on is short, and nobody asks it during a demo. Does the product live on a phone or in a browser? Will an engineer ever open the code, or will the tool stay the only place the app exists? And which language will your first technical hire already write? Those three answers point at different tools. The rest of this page is the evidence behind each one, with the vendor page named every time.
Jump to the three questionsThe short version
Judge it on what you can take out, not on what the demo puts in.
Every builder demos well, and any of them will build a startup app in an afternoon. The differences arrive later: when a first engineer wants the repository, when an investor asks to install the thing, when a vendor changes its plans. So judge on three published facts. What the tool outputs, how that output leaves, and whose developer account the app ships from. Each one is written down by each vendor, and you can check all three in about twenty minutes.
On those three the field splits cleanly, and the split does not follow price. Bubble's own ownership page says there is no way of exporting your application as code. FlutterFlow's pricing page puts code download on Basic at $39 a month and GitHub push on Growth at $80 for the first seat. Lovable's docs describe two-way Git sync and web apps, which is a different product from a store listing. Every claim below is attributed the same way, to the page it came from.
What a startup actually needs from a builder, in order
Start with speed, then stop using it as a criterion. Every tool in this category reaches a working screen on the first afternoon, so speed does not separate them. What separates them is what you are holding three months later: a repository, or a login to somebody else's editor. A startup app builder that saves two weeks now and costs a rewrite at seed is a bad trade. The demo is the one place that trade is invisible.
So the real questions are narrow. What does the tool output, in a form a stranger can read? How does that output leave, and on which plan? Whose developer account does the app ship from? Can somebody outside your company install it without joining your team? Team size changes how much each answer weighs rather than changing the answers, and the one-person version of this is app builder for solo founders.
Three things do not belong on the list. Template counts, because you throw the template away. Editor polish, because you stop looking at the editor once the app works. And monthly price. The gap between these plans is smaller than a week of contractor time, while the gap between the right and the wrong architecture is not.
Can you take the code with you?
Bubble answers this in writing, and the answer is no. Its page on application and data ownership says you own your data and your app's design. The same page says Bubble retains ownership of the underlying code, and that Bubble apps can only be run on the Bubble platform, with no way of exporting your application as code. Leave, and you rebuild the logic. Bubble says it will help export the design, and user data comes out as CSV or through the API. The page also promises that if Bubble were ever discontinued, its source code would be released under an open-source license so you could self-host it. That is a clear trade, published by the vendor, which is more than most tools manage.
FlutterFlow takes the opposite position and charges for it. Its documentation runs under the heading Own Your Code and says you own the output of your work. FlutterFlow's own generated helpers stay on permissive licenses such as MIT or BSD-3-Clause. The pricing page then puts code download on Basic at $39 a month, and GitHub push on Growth at $80 for the first seat. One detail from their GitHub guide matters before you plan around it. FlutterFlow always pushes to a branch named flutterflow, and anything committed directly to that branch is overwritten by the next push. Custom code lives on a separate branch that you merge yourself.
Lovable is the most portable of the three and also the narrowest. Its deployment and ownership page says you are never locked in, and that you own what you create. Git sync runs two ways with GitHub, GitLab or Bitbucket. The same page says what you are building: projects created from 13 May 2026 use TanStack Start, and older ones use React with Vite. Both are web. That is the fork most mvp app development plans skip. A responsive web app is a legitimate first version and a cheaper one, right up to the point where the plan depends on a store listing.
Can an investor open it on their own phone?
A web app is a link. A phone app goes through TestFlight, and Apple's TestFlight page sets out two routes with very different costs. Internal testing covers up to 100 members of your development team. Each of them has to hold the Account Holder, Admin, App Manager, Developer or Marketing role in App Store Connect. It is immediate, but it means giving an investor a role on your developer team. That is not what most founders mean when they say send it over.
External testing is the route you actually want. Apple's page says you can invite up to 10,000 external testers, by email or with a public link. Your first build has to be approved by App Review for TestFlight before any of them can install it, and builds are sent for review automatically once they are added to a group. So put a review cycle in the week before the meeting, not the night before it. Testers install through the TestFlight app on up to 30 devices, so there is nothing to sideload and no device identifiers to collect.
That leaves one requirement on your tool: it has to get a signed build into App Store Connect under your own Apple Developer account. Bubble's publishing FAQ says Bubble generates the build, uploads it to TestFlight and submits it for review. It puts that at about 45 minutes once your certificates and settings are in place. The same FAQ says Android comes out as an AAB that you upload to Google Play yourself. FlutterFlow's pricing page lists one-click App Store deployment from the Basic plan upward. Check this one on the vendor's page rather than on a comparison post, because it is the claim that goes stale fastest.
Apple Developer, TestFlight: internal and external testing limits
So which one, for which startup
Here is the answer in four lines. Web product: Lovable. Phone app where no engineer will ever open the code: Bubble, with the export question settled before you start rather than after. Phone app and your first engineer writes Dart: FlutterFlow. Phone app and your first engineer writes React and TypeScript, which covers most teams hiring right now: Newly. The output is an ordinary React Native project, the GitHub sync runs both ways, and the build lands in your App Store Connect account for you to submit.
Three honest reasons to pick something else. A free tier, because FlutterFlow and Lovable both publish one and we do not. A visual editor a designer can change things in without a pull request, which is home ground for Bubble and FlutterFlow. And an existing Flutter team, which settles the question by itself. Any app builder for founders that costs nothing to start will look better on the first invoice, and starting there is reasonable.
One thing this page does not decide: what happens if it works. Load, cost per user, on-call, the second engineer. We stop at the choice. Past that point the answer depends on your traffic and your team rather than on which builder produced the first version.
Three questions
Which one fits your startup
Where does the product live?
Who touches the code after version one?
What does your first engineer write?
Newly
A React Native and TypeScript project you own, GitHub sync that runs both ways, and builds that land in your own App Store Connect account for you to submit.
What each one hands you, and where the vendor says so
| Option | What it outputs | How the code leaves | Who submits to the App Store | Where that comes from |
|---|---|---|---|---|
| Newly | A React Native and TypeScript project | ZIP from Settings, two-way GitHub sync, or the CLI | You, from your own Apple account | docs.newly.app |
| Lovable | A web app on TanStack Start, or React and Vite for older projects | Two-way Git sync to GitHub, GitLab or Bitbucket | No App Store step in their docs | Lovable docs, deployment and ownership |
| FlutterFlow | A Flutter project | Code download from Basic at $39, GitHub push from Growth at $80 first seat | One-click store deployment from Basic upward | FlutterFlow pricing page and GitHub docs |
| Bubble | A Bubble app plus a native shell for the stores | It does not. No export as code, data out as CSV or API | Bubble builds, uploads to TestFlight and submits | Bubble docs, application and data ownership |
| A developer you hire | Whatever stack you choose | It is your repository from the first commit | You, from your own Apple account | Your own contract |
Getting a first version in front of somebody this week
Whichever tool wins, the week looks the same. Write the one sentence that says what the app does for one person. Build the three screens that sentence needs and nothing else. Put it on a real phone rather than in a screen recording. Then hand it to five people who are not your co-founder and watch where they stop.
Newly is an AI app builder shaped for that week. You describe the app in plain English and it writes a real React Native and TypeScript project you own. It runs the app on cloud iOS and Android simulators while it builds, then ships it to TestFlight and to Google Play internal testing. It is $25 a month and there is no free plan. New apps start local-first, keeping their data on the phone with no accounts and no server. The agent adds a hosted backend only once the app needs accounts, shared data, syncing or payments, and that brings sign-in, an API service, a Postgres database per environment and file storage.
The part that matters at the exit is the dull part. Code comes out as a ZIP from project Settings, through two-way GitHub sync under Deploy, or with the CLI. An engineer who joins in March can read what you built in October. iOS builds go up to App Store Connect and TestFlight, owner or admin only, and the submit button stays yours. Android publishes to Google Play internal testing, with a standalone production APK if you want one to pass around.
Questions founders ask before picking a builder
There is no single winner, but there is a single test: what the tool outputs and how that output leaves. For a web product, Lovable publishes two-way Git sync and web hosting. For a phone app where no engineer will ever open the code, Bubble is the quickest, and its own docs are clear that the app cannot be exported as code. For a phone app you intend to hire engineers around, pick a tool that gives you an ordinary repository in a language those hires already write.
Describe the app, then put it on a real phone
Write the one sentence that says what your app does for one person. Name the three screens it needs, and decide today whose Apple account presses submit. Then build it and send the TestFlight link.
Start building