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Acid Ape Chess GM Edition - review

This time, an application dedicated to mobile devices came to my review workshop.

Hundreds of chess applications have been created for the popular system named with the friendly term of robot, which are readily available in the Google Play Store.

And while there are so many chess apps for Android, only some of them are worthy of prolonged attention, and the best ones dedicated to serious and ambitious enthusiasts of the royal game - there are even fewer. Among them, the real diamond is Acid Ape Chess GM Edition.

In full name: Acid Ape Chess GRANDMASTER EDITION is a powerful, functional and useful chess suite created for demanding users.

It is a program that has been systematically developed for many years, with regular updates, and has many fans who have expressed their opinions in the Google Play Store.

This review deals with Acid Ape Chess GM Edition version 1.11.1 with an update dated December 27, 2022.

Some data in the table:

Table of Acid Ape Chess GM Edition specifications.

It is worth noting that Acid Ape Chess GM Edition needs Android version 4.4 or later to work, which means that...

...Even very old devices have a chance to be used with Acid Ape Chess GM Edition.

The oldest supported Android system 4.4, code-named KitKat, was released in 2013, which is nine years ago as of the publication date of this review.

I took advantage of this opportunity and for the purposes of the review I used the Asus Transformer Prime TF201 tablet, which premiered in 2012. The aforementioned tablet puts at the user's disposal a 4-core nVidia Tegra 3 processor and, importantly for me, a 10.1-inch screen; working on custom firmware - Android 7.1.2

I also used a modern Google Pixel 7 smartphone (2022 model, Android 13) to among others compare analysis times for specific positions; see the chess engine section of this review for details.

So, is it possible with Acid Ape Chess GM Edition:

  • Comfortably use on an old (and modern) mobile device?

  • Efficiently work and analyze with chess engines ?

  • Conveniently play offline and online ?

  • Fast using the chess databases provided by the developers ?

  • Training ?


The application activates the license, which personalizes purchased copy.

Activation takes literally a moment, and then we are greeted by the main screen of Acid Ape Chess GM Edition.


The first thing that caught my eye was the subdued and non-flashy colors, clear access options grouped in an easy to understand logical way. The app's home screen is not overloaded with information and shortcut icons.

We have three main activities: playing online, using the chess engine(s), and playing a simultaneous game.

After entering the option's menu (icon marked with a red border)...

...There will be a move to the expanded functions that are used most often.

When you click on the button marked with a red border....

...A context menu will expand with functions available depending on what you are currently doing.

The main settings screen is structured clearly and, what positively captured me - it does not contain a lot of different options - but the important ones.

Before we get into a detailed review of the significant capabilities of this program, below are some screens showing the use of Acid Ape Chess GM Edition for various activities.

Engine manager

Select Time Control

Game play #1

Game play #2


Working with a chess database

Working with Openings and Evaluation graph

Working chess engine and notation window

Analysis by chess engines #1

Analysis by chess engines #2

Game review with Evaluation graph

Depending on preferences, user can choose different chessboard themes and chess pieces.

Example #1

Example #2

Example #3

Example #4

Example #5

To summarize this part of the review...

Acid Ape Chess GM Edition interface is ergonomically designed with easy access to main and detailed functions.

Despite being extensive and offering a wide range of capabilities, the application is simple to use and visually appealing. The entire interface was designed and built according to the philosophy: where you are and what you use - there you have access to specific and advanced functions.

I like this approach because it respects the user, who is not bombarded with a hundred functions, messages and shortcuts that are unnecessary for him at the moment.

All operations are performed at a good speed without stuttering or waiting to start. Responsiveness stands at a satisfactory level allowing a comfortable using Acid Ape Chess GM Edition.

The large screen (10.1 inches) is well utilized for the app, which is important given what the purpose of the reviewed program is. Smaller smartphone screens - their are optimal use - as shown in the many images on the developer's website and the Google Play Store.

Acid Ape Chess GM Edition offers a thoughtful, modern and attractive interface.

Only one thing is missing - landscape mode. I'm sure this mode would have been especially appreciated by users of mobile devices with larger screens, who could have had even more opportunities to customize the look and layout of the application to their needs.

I almost forgot one more extremely useful feature, which is especially useful when using a mobile device that has a relatively small screen size (compared to, say, a computer monitor screen).

The application provides the user with the ability to use multiple screens.

One screen.

Two screens; possibility to choose one of two screens.

Three screens.

Four screens.

In practice, this means, for example, several simultaneous analyses, simultaneous games or work with the game database or openings.


Acid Ape Chess GM Edition provides access to three popular online chess servers:

  • FICS (free)

  • ICC (paid)

  • Lichess (free)

We can play as a guest - Anonymous.

We can also use the servers as a person with a registered account, in which case our progress is recorded (e.g. rating, participation in tournaments, etc.).

There is also a Player Search function.

Every game played, regardless of the type of account used, is automatically saved in a chess database locally accessible on mobile device. There will be more about this later in the review.

In addition to playing with human opponents or engines (legally play on some servers; must be clearly marked), you can watch live games or interesting events, such as tournaments, championships.


You can play against another person, you can also set a position before the game starts, you can also import a position / game, you can play several games at once and...

...Finally, you can play against the chess engine(s) in one or more games at the same time.

Of course, what a dubious pleasure it is to play against a chess monster like Stockfish, for example, when you can use a chess engine specifically designed to play for fun or training. I am referring to the Rodent chess engine.

I encourage you to read the review of the Rodent chess engine.

Rodent is one of the many chess engines that the Acid Ape Chess GM Edition developer is officially making available for download. It is a very simple operation, which I described later in the content of this review. Rodent, once downloaded, is immediately ready to start playing and is 100% compatible with all the features of the reviewed application.

It is worth adding, there is no obstacle to use any other chess engine.

The user can choose to play from a standard or specific position, and can also choose to play in the Chess960 format also known under name Fisher random chess.

The application allows you to select a Opening Book. You can use the default one used by a particular chess engine or...

You can choose an Opening Book available online provided by the developer.

Rodent chess engine offers a significant number of different personalities to play with. Personalities are placed in catalogs with appropriate names.

Example of famous and well-known personalities:


Strong league players:

Club players:

Learning Players:

Fun personalities:

You can choose or set your time to play.

An ongoing game between Darius (Myself) and Sam. Sam is one of the personalities of the Rodent chess engine.

During the game, you can pause the game or quit it. You can turn on the engine or use all the other options offered by the app.

You can also start a duel of chess engines on one or more chessboards simultaneously and watch them struggle.

Chess engine game in Chess960 format.

The greater the hardware resources of your mobile device, the more chess engines can play simultaneously.

The struggle of chess engines can be very interesting; I think that if the developer introduced in future releases of the program the possibility of playing tournaments by chess engines, it would be welcomed with satisfaction by many fans for such computer duels :)

Local Chess Database

As I mentioned earlier, the app automatically saves all games to the storage of the mobile device. This is convenient because the user does not have to remember it every time...

...And can go back to them - recent games.

The basic data of each game can be edited, and player data can be managed.

Player manager.

Edit Player.

Add Player.

My games base - manage.

Edit Player window.

Game Properties editor.

The available functions allow use the most important operations on the data in the local chess database (in the device's storage) including sorting by various criteria.


The application, through the Online / OTB menu, offers access to a pretty large database of chess players and their games (more than 3 million).

The application offers a number of ways to search...

...And retrieve information.

This is helpful because you only need to type in a few letters of a last name, for example, and players with a name containing the phrase you type in are displayed.

Filter games.

We can treat each game from the database in the same way as a game stored locally on the device: view, analyze, annotate, etc.

Some GM Wesley So games.

One of the GM Jan-Krzysztof Duda beautiful game against GM Anish Giri.

The online chess database is a useful module in the reviewed application. The data is current and updated. The user has access to the games of not only famous chess players, but also to matches and tournaments played today and in the past.


The application has pre-built three chess engines.

Although these engines differ in strength, they have one thing in common: they can play spectacular chess.

  • Arasan, a great chess engine, actively developed for more than 25 years. It ranks among the top in terms of strength, far surpassing any human in this regard.

  • Cheng, a chess engine that plays at the level of world chess champion Magnus Carlsen.

  • Scorpio, a sophisticated chess engine using the Monte-Carlo Tree Search algorithm, which makes it an interesting partner for grandmaster-level analysis.

The application offers the possibility to easily download other interesting chess engines, which will be immediately available for use.

The free Texel chess engine is highlighted, and in addition...

The developer has prepared a free download of modern chess engines updated to their latest versions.

After making a selection, we will be taken to the Google Play Store to download and install.

This is a very good solution, as the user is assured of downloading chess engine(s) from a legitimate and verified source, which are specially prepared to work with Acid Ape Chess GM Edition.

Once the installation is complete and you return to the application, all chess engines will be automatically imported and ready to use

They will be visible on the main screen and of course in Engine manager as well.

One of the unique and very useful features offered by Acid Ape Chess GM Edition is the use of chess engines using the CECP protocol (Winboard / Xboard).

The CECP protocol is mostly used by older chess engines, which may not play at the TOP level of today's engines but have many useful options to offer, such as training and/or a unique style of play.

Such engine include the previously mentioned Scorpio. It is also Phalanx, which I installed using an Other option available in window Add Engine Package.

The application also allows you to use a chess engine that you have purchased from Google Play; then it will automatically be imported. This is what happened with the Komodo 13.1 engine that I once purchased.

Phalanx and Komodo appeared in the list of available chess engines.

I created this review at an interesting time, when the latest versions of popular and powerful chess engines appeared: Lc0 and Stockfish. I welcomed the update of the above-mentioned engines by the developer immediately after their release. Bravo! This is what the approach to the Customer should be.

Looking at the chess engines offered by the developer as a whole, I think it's a good choice. We have engines that play interesting styles, with a different cross-section of playing strengths including the strongest and also real gems like Rodent - a great partner for training and playing.

Of course, the application offers access to chess engine settings, through which we can set the engine to work according to our preferences.

Example #1, accessing Komodo settings.

Stockfish 15.1 Strength

As of the date of writing this review, Stockfish 15.1 ranks first in most chess engine ranking lists. So let's see how Stockfish 15.1 performs by analyzing 10 selected positions that are used for this purpose on the blog.

Mostly, I have chosen games from games played by humans. I use a bundle of these positions for program reviews and chess engine tests. My goal is to test the Stockfish 15.1 on 10 positions giving it a maximum of three minutes of thought per move. I have assumed that these will be positions played by people who have allotted up to a few minutes for a move. Therefore, I did not take into account positions created in correspondence games. I also wanted to see how this chess engine would perform on an old tablet and, when finished, compare with the results achieved on a modern smartphone.

During testing, Stockfish 15.1 used 3 CPU cores and (only) 16MB Hash table.

Let's see what results it achieved on a vintage tablet.

SF15.1 did not find the winning 1.Qxb5.

After 5 minutes and 5 seconds of thought, it sees a big advantage for white.

2 minutes and 6 seconds, that's how long it took SF15.1 to find the beautiful 1.c5!

Only 14 seconds.

That's all it took for SF15.1 to find the amazing strike of black Rook 1...Rxb3!!

And this time SF15.1 finds the best move to equalize the game. 1...Qe3 pointed out after 24 seconds.

Even faster after only 9 seconds, SF15.1 indicated a winning move in the following position. After a few more seconds, 1...Qd3 was rated even much higher by this engine.

SF15.1 did not find the strongest 1...Nc7.

This time SF15.1 also failed to indicate the impressive and winning 1.Qf6+

And this following position proved too difficult for SF15.1 to indicate the strongest move 1.Kf2!

It took 17 seconds for SF15.1 to show an impressive sacrifice of white Rook 1.Rxe7!!!

The last position, extremely difficult for chess engines and for SF15.1, remained unresolved.

I am impressed.

Stockfish 15.1 on an old tablet solved 5 out of 10 difficult chess positions!

In comparison, Stockfish 15.1 on the Google Pixel 7 smartphone solved 9 out of 10 positions (it did not solve position number 10), most of them three to four times faster.

Curiosity: on iPhone 12, an almost 3-year-old smartphone (counting up to the day this review was published), Stockfish performed slightly better as the Stockfish on Google's smartphone.

I'm glad to see that even on an old mobile device, the modern chess engine running on Acid Ape Chess GM Edition achieves good results.

New smartphones mean new processors and chips; on such hardware Stockfish is able to play and analyze at high level.


Manulan Annotation.

Certainly, the attentive Reader has noticed that access to the application's functions is easy and clear; annotation is no different.

The moves in the chess game annotation can be edited and comments can be added / modified.

Few examples.

Any annotations entered by the user will be automatically saved by the application.

Automatic annotation.

This is one of the most interesting and useful features with the engine(s).

Any chess engine can be used; below Stockfish with MOVE COMMENT disabled.

The same chess engine with MOVE COMMENT enabled.

And below is Komodo with an analysis time of 3 seconds per move.

Depending on the time per move set by the user, the application calculates how long it will take to analyze the entire chess game.

The longer the thinking time is set, the more accurate the chess game analysis will be and the longer it will take.

Once started, you can watch the progress of the analysis and the annotations made in real time.

22% of the analysis and annotations entered.

70% analysis, entered comments and annotations. Particularly important movements are highlighted with shades of red.

Analysis completed. Annotations done. The process took exactly the amount of time the application calculated before it began.

It is worth mentioning that the program helps the user when working with different modules by communicating depending on what the user is currently doing. For example, I decided to run an automatic annotation for a selected chess game, which caused the application to display a window indicating that the annotation of this game had already been done.

It's a good idea to run the chess engine(s) to check and see what it thinks of our move(s).

In addition to automatic annotation, the application marks movements with colored arrows (a detailed description is in the application's manual).

The application, along with the chess engine, can prepare a graph for us to visualize the progress of a chess game.

The user can choose from the available engines to re-analyze...

...And prepare a visualization of the game on a graph.

While reviewing the game, you can work on and practice chess openings.

The application also allows you to find games and chess players who have used the given opening.

You can also use different functions at the same time, such as the Opening module and Evaluation graph.

Chess opening module and analysis by chess engine.

Chess engine notation and analysis window.

Three lines of chess engine analysis and notation window.

Analysis by three different chess engines.

Analysis by three different chess engines and Evaluation graph created using these three engines.

Evaluation graph in a larger window.

The application uses a database of chess endings (EGTB), which it can access online. This is a convenient solution, helping to quickly check whether, for example, in a particular position either side is winning or can get a draw.

Acid Ape Chess GM Edition gives the user a very large number of possibilities to obtain analyses. All of them can be very effective training tools.


A large number, as many as 900 puzzles at three levels of difficulty.

900 fun and relaxing opportunities for exercise or just for enjoyment.

The app meticulously notes our progress and, of course, allows us to turn on the chess engine if we need to.

Below are a couple of screenshots.

Verification by chess engine.

It is possible to reset the results.


Acid Ape Chess allows you to play on a connected physical chessboard.

A physical clock can optionally be connected to that board.

Unfortunately, I do not have access to the aforementioned devices (DGT). As a result, I do not have the opportunity to review the application in terms of the use of the physical chessboard and clock.

If someone will be so kind as to share these devices with me, then I will be happy to expand this part of the review.


This section is also built with great attention to detail.

From the app and from the website there is access to the detailed manual, which is continuously updated with newly introduced features.

You can get in touch with the developer or read about what's new in the next versions of the reviewed program. You can also watch an introductory video of the app, which can be helpful especially to new users.

Customer service is fast and at a high level. I am very pleased with this, because in addition to the actual help, it leaves a very good and professional impression.


Here's what the Acid Ape Chess developers wrote on their website.

Source: app website (2022-12-31)

Is it possible with Acid Ape Chess GM Edition:

Comfortably use on an old (and modern) mobile device?


Efficiently work and analyze with chess engines ?


Conveniently play offline and online ?


Fast using the chess database provided by the developers ?


Training ?


In the category of programs that I had the opportunity to review,

Acid Ape Chess GM Edition is the biggest and most positive surprise of 2022.

Even more so, because it is mentioned about a program designed for mobile devices.

This is the best example of how excellent a program that runs on smartphones and tablets can be and is being developed. And how many possibilities it offers.

Acid Ape Chess GM Edition has unique features in the segment of chess programs for mobile devices, such as using multiple chess engines at the same time, working with many workspaces and chess engines using the most popular communication protocols (UCI & CECP).

The strength of Acid Ape Chess GM Edition is its ability to combine different functions/modules into a logical whole giving the user a powerful tool - chess suite - for analysis, training or simply for fun.

There is no doubt in my mind that...

Acid Ape Chess GM Edition offers much more capabilities than most desktop chess programs, leaving far behind competitors from mobile devices.

I'm always happy when chess services, engines or software are designed for the largest possible public. This is no different with Acid Ape Chess GM Edition, which runs on even the oldest devices running on Android. And how it works! Fast, smooth and without interruptions. I found no hangs or unexpected closures. It always worked well and without errors. The same is true on a modern device like the Google Pixel 7.

The developer has been regularly taking care of its product for years, updating and adding new features. Not surprisingly, Acid Ape Chess GM Edition is a premium application highly rated in the Google Play store by users. I would like to see this excellent program appear in the Apple store; I think it would find many buyers among chess enthusiasts using iPhones and iPads.

It's worth mentioning that the developer provides a free Acid Ape Chess from the Google Play store, which, although lacking some of the features available in the GM Edition, gives you the opportunity to explore and test the program - which I strongly encourage you to do.

All features of the program and its full version is available in the Google Play store here.

Acid Ape Chess GM Edition, is an application created by people who understand perfectly how a modern chess program should look, work and what it should offer. And this is something that we - the users - can benefit from.


2 comentários

Benjamin Bradley
Benjamin Bradley
04 de jan. de 2023

Simply on your great review (to be honest, most of your reviews are well done), I bought this app and so far I have been extremely impressed. Thanks for your hard work in digging into tools and resources that would be useful for chess lovers.

04 de jan. de 2023
Respondendo a

Benjamin, I'm very glad that you found the review useful :)

Thank you very much for your kind and motivating words!