1. Lovable— free tier available, from $25/mo
An AI software engineer you chat with: describe a web app and it writes, previews and deploys it, with Supabase and GitHub wired in.
Lovable is the best pure chat-to-app builder for founders, and if you have already validated your idea it is a better use of $25 than almost anything else. Its blind spot is structural rather than technical: it will build the wrong product as beautifully as the right one, because nothing in the product asks whether anyone wants it. kitty.build answers that question first — nine boards, live research, a cited verdict that is allowed to say no — and then builds and operates the survivor. If you are certain about the idea, use Lovable. If you are certain because you like the idea, validate it first.
- Best at:
- The fastest path from a sentence to a working, good-looking web app in this whole set
- Watch out for:
- Credits burn fastest when you are debugging, which is exactly when you can least afford it
- Best for:
- Founders who already know what to build and want the fastest, prettiest path to a working web app.
- Pricing:
- Free $0 · Pro $25/mo · Business $50/mo · Enterprise Custom
Read the full kitty.build vs Lovable comparison →
2. Bolt.new— free tier available, from $25/mo
StackBlitz's in-browser AI app builder: prompt it and a full-stack app is written, run and deployed without leaving the tab.
Bolt.new is the best free way to find out whether an app idea is buildable, and the token rollover on Pro is the fairest metering in the builder category. What it does not do — like every builder here — is tell you whether the thing is worth building; it will happily burn 10M tokens on a product with no market. Use Bolt to answer "can this be built and how hard is it". Use kitty.build to answer "should it be", and then to keep the answer alive after launch with a site on your domain, code in your repo and daily operating cycles.
- Best at:
- The most generous free tier of any AI app builder here — 1M tokens/month without paying
- Watch out for:
- Tokens are consumed by failed attempts, so error loops are expensive
- Best for:
- Prototypers who want to try five app ideas this week without paying, and who are comfortable steering an AI through the rough edges.
- Pricing:
- Free $0 · Pro $25/mo · Teams $30/member/mo · Enterprise Custom
Read the full kitty.build vs Bolt.new comparison →
3. v0 by Vercel— free tier available, from $30/user/mo
Vercel's AI builder for full-stack apps and UI: prompt or sketch a screen and get production-grade React, Tailwind and shadcn/ui code that deploys to Vercel.
v0 produces the best frontend code in this comparison and it is the right choice for anyone technical who lives on Vercel. It is also the most explicitly a tool rather than a co-founder: per-seat pricing, a seven-message free tier, and no opinion at all about whether your product should exist. kitty.build sits at the opposite end — it will argue with your idea before it writes a line, and it keeps running the venture after launch. If you can code and want leverage, use v0. If you want judgement and operations, that is a different purchase.
- Best at:
- The cleanest, most idiomatic frontend code of any builder here — a real developer would ship it
- Watch out for:
- Priced per seat, so a two-person team pays $60/mo before anything is built
- Best for:
- Developers and technical founders who want the AI to produce code they would have written themselves, on a stack they already deploy to.
- Pricing:
- Free $0 · Plus $30/user/mo · Business $100/user/mo · Enterprise Custom
Read the full kitty.build vs v0 by Vercel comparison →
4. Base44— free tier available, from $16/mo (annual)
A Wix-owned AI app builder for non-developers: describe what you need and it constructs a working app with auth, database and hosting attached.
Base44 is the friendliest and cheapest way for a non-technical founder to get a working app, and Wix's ownership removes the will-this-company-exist-next-year risk that hangs over smaller builders. The credit ceilings are tighter than the prices suggest, and like every builder it has no opinion about whether the app should exist. kitty.build's bet is that the opinion is the expensive part: a free nine-board validation with citations comes first, and only the surviving idea gets built and operated.
- Best at:
- The cheapest genuine paid entry point among the AI app builders at $16/mo annual
- Watch out for:
- 25 free message credits a month is a thin trial — you will hit it in an afternoon
- Best for:
- Non-technical founders and operators who want an internal tool or a simple product built without touching a code editor.
- Pricing:
- Free $0 · Starter $16/mo annual · Builder $40/mo annual · Pro $80/mo annual · Elite $160/mo annual
Read the full kitty.build vs Base44 comparison →
5. kitty.build— free tier available, from $17/mo
An AI co-founder that validates an idea with nine researching boards, then builds, ships and runs the venture that survives.
kitty.build is the only tool in this set that both refuses to build a bad idea and builds the good one. Nine boards research the live web, cite what they find and return a GO / PIVOT / NO-GO verdict for free; if the verdict is GO, the same product ships the site on your domain, writes the code into your GitHub repo and runs daily cycles where a task only counts as done with evidence attached. The trade is that it is a subscription and it is opinionated. If you want a single document, or you want to art-direct every pixel yourself, something else on this list fits you better.
- Best at:
- The first verdict is free and it is allowed to say no
- Watch out for:
- It is a subscription — if you only want one document and then silence, a one-time report is cheaper
- Best for:
- Solo founders and small teams who want the idea checked honestly first, and the surviving one actually built and operated without hiring.
- Pricing:
- Free $0 · Spark $17/mo · Portfolio $66/mo · Studio $166/mo