Comparison of AI-Prototyping tools for product leaders

First of all, it is important to clarify my use case, because it also explains how I evaluated the instruments below. I have three main requirements:

• Like many PMs, I own an established product, so often my goal is to copy the already-made interface and “imitate” a new feature (like I did in this article with Spotify). So then I can look at it myself, showcase it to stakeholders, or even add to the PRD as a visual example.
• Like many other IT professionals, I'm curious about the new AI technology and exploring it by building tools for my own use. Tools can not work on "just UI”; they need backend/databases, thus my second requirement was that the AI tool supports full-stack development without me touching the code.
• Finally, (unfortunately), I don’t have a lot of free time, so the last condition is that I want to have as much out of the box as possible. Everything (!) can be built/coded/hacked together: there are even magicians who can “vibe-code” by asking questions to ChatGPT and then assembling it all themselves. I bow to them, but I've always personally hated and still do “logistics” to make things work; I like the act of creation itself. And yes, I don’t have time.

Finally, I don’t care about brands: Replit, Lovable, Bolt, etc. are equal to me if they do the work promised at a reasonable price. I also don’t care about marketing: some are more aggressive and hype-y in their tone of voice, some are more humble - I ignore it.

Below is the comparison table. The rows are the tools (Replit, Lovable, etc) and the columns are what these tools can do from the perspective of non-tech people:

• Can they generate Frontend / UI (pages, widgets, etc)
• Can they generate Backend (logic, external API integrations e.g. OpenAPI)
• Can they create and manage Databases so that the app can have memory, and do it for real traffic, not only for the preview environment
• Can they publish the creation to the rest of the Internet so anyone who has a link can use it (this should include not only UI, but also the underlying logic: backend and databases).

Below the table, I also explain how the tools deliver on the three requirements I have.

All top tools perform similarly here - they all can generate a decent frontend. Have you ever thought why? There is an underlying reason, and it is quite intuitive.

The front-end / UI itself consists of the three main pillars:

• HTML skeleton (buttons, images, text blocks, etc)
• CSS style definitions (buttons are rounded or with sharp corners, with shadows or not, etc),
• JavaScript makes them alive (click on a button to open a map).

Any interface you see is just a combination of these three DNA blocks, and the complexity is quite limited: despite the visible variety of websites you see, they are all just a sequence of a title, subtitle, text, picture, buttons, and links. And yes, it can be a long page, but it just means it has a lot of text, buttons, images, etc, which doesn't make it more complex from code perspective. General-purpose LLMs (Claude, ChatGPT, etc) generate this code (which is just text) really well, and AI-prototyping tools capitalize on that.

So, my verdict here is that all top tools can handle frontend development. But you might say that "tool X copies the UI better than tool Y". Still, I’d say that for quick prototypes, it is not so important, and if it is, you can always fine-tune your clone either by:

• Tweaking the result (“Fix this, add the shadows here, change blue to deep blue here”, etc.)
• Or, more fundamentally, by changing the component library (in simple words, a collection of elements you want AI to use). It makes sense: if AI uses the same buttons as the target UI, then your copy will be closer to the original.
• Finally, you can get as precise as uploading an original Figma file to the tool (there are plugins to do this, also).

As usual, you balance between "time spent" and "quality".

This is where we have the biggest difference. First of all, the top tools (Replit, Lovable, Bolt) can deal with simple backends (e.g., for a to-do list app, you need to be able to create a task, update it, and delete it - a very simple database with simple operations on it).

It becomes less shiny when you want to unleash your creativity and say something like: “Now add an ability to pull my tasks from this VoiceAPI (which transcribes voice into text) and then send all tasks to OpenAI API to prioritise and create a personal week backlog.”

These are quite adequate requirements: after all, there are thousands of APIs around the world, and you want to benefit from them (without writing code yourself). Let's compare how the tools handle this situation:

• Replit, in this case, acts as a “developer sitting next to you” - it will figure out requirements and start to integrate first with the VoiceAPI, and then with the OpenAI API. This is exactly what I need for my case: I generate ideas, and the AI agent takes care of the coding part.
• Lovable / Bolt will generate some stubs. For the OpenAI API, it might even work immediately, but for non-famous (or more complex) integrations, it will most likely fail. So, there is a high chance you'll need a real developer to finish it for you. I don’t have a developer, and I don’t want to be one myself.
• Coding assistants (Cursor, Copilot) can create any code you need, but you should know what to do with it and how to make it run on your own computer. Which is hard and time-consuming for most of us, non-tech folks.

As I mentioned above, everything can be done; the question is, how much free time/passion you have. In this sense, Replit seems to be the most rounded option. All the other tools require actions from you: as lightweight as setting up an external tool (Supabase) and as heavy as figuring out peculiarities of API integration, or as insane as figuring out your own cloud hosting / publishing while in other tools is just a button click.

For my use cases, I prefer Replit: it handles both simple UI mocks and allows me to stay away from code when I have non-trivial ideas. It also allows me to “settle” with one tool instead of having a tool per use case, which is quite an annoying (multiple billings, multiple accounts, multiple UIs to learn, etc).

I also want to clarify that it doesn’t mean Replit is the best in general; it just means it is the best for my needs.

• If you need just simple UI mocks and you love the Lovable (pun intended) interface and speed, go with it.
• If you enjoy Bolt's style, go with it.
• If you love getting your hands dirty with code and hacking it all yourself, Cursor is your friend.

The most important thing is that you (a) have good ideas, (b) enjoy the process of creation, and (c) ship something at the end.

If you want to learn a structural approach to AI-creation, then check the "Full-stack AI-prototyping for Product Managers and founders" course. There, you will build three cases yourself, add 10+ features, and do it all from the very basics to introducing technology to pro-prompts and complex integrations. Learn by doing, that's the only way!

I hope this was useful 🤖

Author: Vladimir Kalmykov, Lead PM at Booking.com