ServeLab (formerly Bert)

ServeLab (formerly Bert)

A Tennis Coach in Your Pocket

7 ratings
5 reviews
Free
In-App PurchasesWith Ads

Details

  • Released
  • Updated
  • July 31, 2025
  • June 25, 2026

Features

ServeLab (formerly Bert) screenshot #1 for iPhone
ServeLab (formerly Bert) screenshot #2 for iPhone
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About

Film your tennis serve and receive instant AI-powered feedback on your technique. Identify mistakes and get actionable advice to improve your game. Your personal tennis coach is now available on your phone.

AI-powered serve analysis
Mistake identification
Personalized improvement tips
Video recording and feedback
Pocket tennis coach
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What's New in ServeLab (formerly Bert)

3.0.0

June 25, 2026

Bert is now ServeLab - a completely upgraded way to improve your serve! Not only do we have a new design, we also have new tools to help you get the most out of our AI analysis and improve your swing.

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Subscription plans

Bert Monthly

Unlimited access to Bert

$29.001 Month
How to cancel ServeLab (formerly Bert) subscription ⁉️
3

In-App Purchases

$67.00

One lesson with Bert

Two uploads - before & after analyses

User reviews

zu teuer!

viel zu teuer! schade weil an sich eine gute idee. 350€ nur für aufschlag ist zu viel. das muss auch günstiger gehen vielleicht mit werbung ansonsten buche ich mir einfach einen trainer und hab für weniger geld mehr davon.

300$ per year paywall

This buggy app which doesn’t work is behind a 300$ dollar per year subscription. Insanely steep price for something that doesn’t help your game at all. Much less worth 30 dollars a month. Feels like a rush job. There are definitely better alternatives to this.

The worse part is the AI ‘support’

Uploaded a video of my serve to the app, and the feedback I got was ‘no mistakes’.

The support team consists of an AI robot waffling on about general issues. It’s told me to add better prompts ‘comparing it to top pros’, (fairly sure there is no option to add prompts) ‘take a side shot for more accurate analysis’ (a direct contradiction to the instructions). ‘The app is probably analysing general flow and not biomechanics’.

The app is also really clunky and slow.

Don’t trust these slick YouTube videos. So far it’s been a complete waste of money.
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Great idea, lacking execution so far

I echo the other review, though maybe it has gotten better by now with a larger dataset to work from. When I used it in Oct 25, it was not able to accurately distinguish different parts of my body and joint angles even if I set up everything perfectly with good lighting and distinguishable clothing. I thought I was going crazy trying everything to change my stroke until I realized it was not reading my stroke right in the first place. Additionally, although Mark is a good researcher and can identify problems with technique, he isn’t an expert coach in fixing those problems, so the tips for improvement are quite limited.
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underdeveloped

his product feels completely raw and underdeveloped — hard to believe they’re charging a premium for it. The so-called “AI” serve evaluation gives ridiculous and inaccurate feedback; I even tested it by recording a player who didn’t serve at all, and it still produced detailed “issues” in every stage of the serve. It’s a great idea in theory, but in its current state, it simply doesn’t work. Definitely not worth $60 a month — and by the way, the video processing alone takes a good 15 minutes.
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Response from developer

Hey thanks for the feedback. So Bert was training on videos of people serving, and it assumes that when someone uploads a video, there's someone serving in it. So when you uploaded a video with no actual serve, Bert was still looking for all the stuff we training it to look for - that's why you got a long list of mistakes. Bert is basically saying, "Hey I didn't see you do XYZ in this video." In terms of the processing time, we now have it down to under a minute :-) Thanks again for the feedback. Helps us improve Bert. Will

Developer apps

FAQ

How does Bert analyze my tennis serve?

Bert uses AI to analyze a video of your tennis serve. It identifies specific mistakes in your technique and provides actionable advice on how to correct them, helping you improve your game.

What kind of feedback does Bert provide?

Bert provides detailed feedback on your serve, highlighting errors in your form and offering clear instructions on how to fix them. This personalized guidance aims to enhance your serving accuracy and power.

Is Bert available on all devices?

Bert is available on iPhone, iPad, and iPod. The app is designed to work on Apple's mobile operating systems.

What are the subscription options for Bert?

Bert offers monthly and yearly subscription plans. The monthly plan costs $29.00 per month, and the yearly plan is priced at $299.00 per year.

Does Bert have ads?

Yes, Bert contains advertisements. As a free app with in-app purchases, it utilizes ads to support its services.

What is the age rating for Bert?

Bert has an age rating of 4+, making it suitable for young users and above. This indicates it contains no mature content.

How often is Bert updated?

The latest version of Bert was released on March 24, 2026. Updates are released periodically to improve features and performance.

What is the user sentiment for Bert?

Based on the available data, Bert has a rating of 3.0 stars from 3 ratings. This suggests a mixed user reception.