5 Recommended Go Game Review Apps & Software: Analyze Your SGF with AI and Learn from Your Games

“I lost, but I don’t know what I did wrong.” “I want to review, but I don’t have anyone to teach me.” Have you ever felt that way?

If you load your game record into an AI review app or software, you can look back on your game even by yourself.

With AI, you can see the moves where the game swung and suggestions for better moves.

On a smartphone, PlayGo.gg or Igo no Shisho let you review right after a game; if you want to do a deep dive on a PC, KaTrain is a strong candidate.

In this article, we’ll introduce three review apps for smartphones and two review tools/sites for PCs.

Also check what “review” means and the cautions to keep in mind when reviewing with AI.

[toc]

5 Recommended Go Review Apps & Software

The tools introduced in this column that you can use for Go game review are three smartphone apps and two PC tools/sites.

First, let’s compare supported devices, pricing, and what you can do in review.

In this article, we’ll focus on “what you can do in review.”

If you’re looking for an AI to play against, see Recommended Go AI software/apps.

3 Recommended Go Review Apps You Can Use on a Smartphone

The strength of smartphone/tablet apps is that you can review right after a game ends or while you’re out.

You can look back while the frustration of losing is still fresh, so you can search for the cause with your memory intact.

On the other hand, the screen is small, so it’s not ideal for comparing lots of variations side by side.

If you want to sit down and investigate carefully, also consider the PC tools introduced later.

PlayGo.gg｜An AI coach explains in Japanese right after your game

PlayGo.gg is for people who want to handle everything—from playing to reviewing—in a single app.

Games played on PlayGo.gg can be opened for AI review immediately after they end.

In the post-game coach report, you can check accuracy, good moves, and mistakes.

The AI coach points out the moves where you lost points and explains better moves and the reasons in Japanese.

You can also turn mistake positions into practice problems and solve them again.

The app “PlayGo.gg - Go” supports iPhone, iPad, and Android, and can be downloaded for free (with in-app purchases).

You can also analyze games played on other sites or a physical board by uploading an SGF file and having the Go AI KataGo analyze it.

SGF is a file format used to save Go game records.

If you want to use it on a PC, try the page where you can analyze SGFs with AI in your browser.

Even with a free account, you can analyze up to a set number of times per day.

If you want to use it without worrying about limits, you’ll need a paid subscription.

Igo no Shisho｜A one-time purchase app that lets you switch between multiple AIs

Igo no Shisho is an app for people who want to run AI on their own iPhone/iPad and review carefully.

It includes neural networks from open-source Go AIs such as Leela Zero, ELF OpenGo, PhoenixGo, Minigo, and SAI.

KataGo is available as an optional add-on.

It’s a one-time purchase app, with in-app purchases as well.

One thing to watch is your device performance.

The developer clearly states that on older devices, thinking speed drops and misreads of ladders become more frequent.

Before buying, it’s reassuring to check which generation your device is.

SmartGo｜From recording and annotating to analysis, all in one

SmartGo is for people who want to review while recording and organizing their own game records.

It supports importing and editing SGF files and adding annotations, so you can write down what you noticed move by move.

It also has a feature to import a game record from a photo of a board, which is handy if you want to save games played at a Go salon or tournament.

It works on iPhone, iPad, and Mac, and the download is free.

However, the free version and Pro have different available features.

• Free: record/replay/annotate SGFs, AI play up to 13x13
• Pro (annual/monthly/one-time): analyze games with KataGo, AI play on 19x19, import game records from photos

Using AI to investigate bad moves assumes you upgrade to Pro.

A good approach is to first try recording game records with the free version, and if you like the controls, consider Pro.

2 Recommended Go Review Tools/Sites You Can Use on a PC

On a PC, you have a larger screen, so you can review while looking at the win-rate graph, the board, and variations at the same time.

If you want to spend 30 minutes or an hour analyzing a single game, a PC is a good fit.

For installed software, higher PC performance generally means faster analysis.

You can also choose to use review features built into online Go servers without installing anything.

Here, we’ll look at one representative option for each.

KaTrain｜Free review software where mistakes are shown by color

KaTrain is often the first candidate when you want to start free AI review on a PC.

KataGo is bundled from the start, so you don’t need to prepare an AI separately.

KataGo is an open-source Go AI with strength beyond professional level.

It supports Windows, macOS, and Linux.

On Windows, you can just download the executable from the distribution page and run it—everything you need is included.

The menu also supports Japanese display.

When you load an SGF, how many points you lost on each move is shown by the color and size of a dot on top of the stone.

The feature that automatically creates an SGF summarizing only the big mistakes is also convenient.

The developer advises that kyu players should first focus on the large red or purple dots.

Rather than chasing small mistakes, start by reviewing the important points where the game swung.

OGS (Online-Go.com)｜An online Go server that automatically adds an AI review when the game ends

OGS (Online-Go.com) is for people who want to do online play and AI review in the same place without installing software.

It’s a free online Go server, and you can also switch the interface to Japanese.

Games played on OGS are automatically run through a free AI review when they end.

A win-rate graph is shown under the players’ names, and you can check the moves where the game swung significantly (key moves).

You can switch the graph between win rate and point difference, and the move the AI considers best is shown on the board with a blue circle.

In the free review, the AI only examines a few key moves in detail.

The following two are features for paid site supporters:

• Full review that examines every move
• Upload and analyze SGFs from games played on other sites or a physical board

What Go “Review” Means

Go review means looking back on a game after it ends and checking which moves were good and which were bad.

Doing a review after playing is essential for improvement.

Here, we’ll explain what review means and what you can learn by using AI.

Review means looking back on a game after it ends

Review means looking back on the game you played and studying the turning points that decided the result and other promising alternatives.

Reviewing together with your opponent is also called a “post-game discussion.”

Review leads to improvement because it helps you notice your recurring mistake patterns.

For example, tendencies like “I always get stones captured in the middlegame” or “I lose points in endgame yose” can’t be seen from just one game.

After reviewing several games, you start to see the same kinds of failures.

In the past, to know which move was bad, you needed someone stronger than you to look at it.

Now, with AI review apps and software, you can look back on your own even without a partner.

What you can learn from AI review

With AI review, you can understand the flow of the game, the moves where you lost points, and better moves.

Let’s go through them in order.

• Flow of the game: With a win-rate or point-difference graph, you can see at a glance where the game swung
• Moves where you lost points: Where the graph drops sharply are the moves that lost points. Some apps mark them as mistakes
• Better moves: The AI shows candidate moves and the continuation afterward (variations)

A game you thought was “I got reversed in the endgame” might turn out to have been a big loss from a single move in the opening.

With a graph, you save the effort of searching for which positions to review.

To have AI analyze your game record, you need the game record data.

Go game records are commonly saved and loaded as SGF files.

You use an SGF saved from a playing app or site by loading it into a review app/software.

It’s also good study to load and review professional game records, not just your own.

If you want to get game records, see How to watch pro game records for free.

Two Cautions When Reviewing Go with AI

AI review is convenient, but if you look at it the wrong way, it can be harder to improve.

The two things to watch are: “Don’t memorize AI moves by rote” and “Don’t worry too much about small win-rate fluctuations.”

Both are ways to avoid accepting the AI’s answers as-is and to leave time to think with your own head.

Don’t memorize AI moves by rote

Only adopt AI-suggested moves that you can explain in your own words.

If you only memorize the move, you can’t use it when the shape is slightly different.

AI will show an answer like “this is best,” but basically it won’t teach you the reason.

Imitating it without understanding the reason won’t be very effective.

A recommended order is to first think for yourself about “what was wrong,” and then look at the AI’s answer.

Where your prediction differs from the AI’s answer is where you’ll find new discoveries.

If you really can’t understand the reason for a move, you don’t have to force yourself to memorize it—it's fine to put it on hold.

Don’t worry too much about small win-rate ups and downs

In review, it’s enough to look only at the moves where the game swung significantly.

AI will show the best move even for a few percent difference, but what decides wins and losses for kyu players to low-dan players is usually the big mistakes.

If you try to examine every move, reviewing a single game will take a long time.

At first, try revisiting just a few moves centered on where the graph dropped sharply.

Frequently Asked Questions About Go Review

Here are answers to common questions about Go review.

If you’re curious about how to proceed with review or how to handle games played in other apps, use this as a reference.

How should I proceed with post-game review?

For post-game review, proceed in the order: “review yourself → confirm with AI → replay.”

1. Right after the game, recall the positions where you think you played badly
2. In a review app, look at the win-rate graph and identify the moves where it dropped sharply
3. Play out the AI’s candidate moves on the board yourself and think about why they’re better

If you take time to think on your own first, the AI’s answers are more likely to stick in your memory.

Try reviewing not only games you lost, but also games you won.

Even in games you won, you’ll often find mistakes that your opponent simply overlooked.

Can I review games played on GoQuest or Fox Go Server?

If you can save the game record as an SGF file, you can load it into the review apps/software introduced in this article and review it.

The steps for saving or sharing game records differ by playing app.

Since app updates can change the procedure, check each app’s game record screen or help.

How long your game history remains also differs by service, so it’s safest to save games you want to review as early as possible.

The same idea applies to games played in other apps.

Whether you can export to SGF is the dividing line for whether you can review it.

Is AI review useful even for beginners?

AI review is useful even for beginners.

However, the key is to narrow what you look at.

You can review 9x9 or 13x13 games as well.

It’s enough to look only at positions where you got stones captured or where the game swung significantly.

You don’t need to chase every detailed variation the AI shows.

Even just realizing “If I had defended this stone one move earlier, it wouldn’t have been captured” can help in your next game.

If you’re choosing a Go app from now, also check Free Go apps for beginners.

Summary

Go review means looking back on a game after it ends and checking the good moves and bad moves.

Today, if you use AI review apps/software, you can confirm the moves where the game swung and better moves even on your own.

The five review apps/software introduced in this article are:

• For smartphones: PlayGo.gg, Igo no Shisho, SmartGo
• For PCs: KaTrain, OGS

When reviewing, the key is not to memorize AI moves by rote, and to focus only on the big mistakes.

Don’t try to understand everything—start with just a few moves per game.

First, play one game and try reviewing it on the spot.

With PlayGo.gg, you can open AI review immediately after the game ends.

Give it a try.