Chess Openings Pro

Chess openingsReview details:
App version: 4.1.1
Device:  iPad 3
Operating system: iOS 9.3.1


A well designed and valuable tool for club players wanting to brush up on their general opening play though it may be somewhat limited for more in-depth study of particular openings 

Chess Openings Pro is an iOS app from Tom Ashmore for use on tablet and mobile devices.The Pro version of the app, as it’s name suggests the fully featured edition and costs £2.99. There is a free trial ‘Lite’ version (Chess Openings Explorer) which has some important restrictions which are outlined where relevant in this review. It is also worth saying, don’t confuse the Lite version of this app with the similarly named android app (reviewed here). They are developed by different people and are independent apps.

COE_mainChess Openings Pro as its name suggests, is a tool for exploring and learning about the chess openings. The app enables openings to be studied in a range of different ways several ways; it does this primarily in two ways using:

  • information from a database of opening moves which is drawn from the results of a large pool of games;
  • an integrated chess engine to provide detailed analysis of specific positions and the option to play out games from openings of the user’ choice.

A database of moves with associated frequencies of wins/draws/losses (w/d/l) is a commonly used format in established chess database applications. The app is not particualy innovative in that it uses the well established approach of  visually representing opening move choices in the form of a ‘tree’ of individual moves from the current board position. These moves are shown with associated ‘performance’ information relating to the move such as the number of times it has been played, and the scores in terms of game outcomes (For example 50% of games playing the move from this position where won by white… etc).  But it ain’t broke don’t fix it – this is an effective approach as it enables the user to quickly see which are the most frequently played moves from a given position and what the also which produces the best results.


An app dedicated to chess openings is only really as good as the database it uses. The volume and quality of the games are key factors to consider:

  • too few games and the database is too small to give sufficient information about individual moves or coverage of opening moves. (for example you can’t conclude much if there are only the results of says 5 games from the current position!)
  • if the database is made up of games between weak players or games played at very fast time controls (eg bullet or blitz) the quality of the moves played will generally be low and the results in terms of the game outcomes (w/d/l) will be similarly impacted (garbage in garbage out)

COEPro2Chess Openings Pro stacks up pretty well in terms of its database. The Pro version uses over 1.9 million ‘high level’ games. Whilst ‘high level’ is not defined, at least the importance of quality is recognised and the volume is good enough that it doesn’t feel that positions are reached too quickly where there are no games left . (Note the database in the Lite version is a third of the size). One specific feature which is rare to find in this type of app but which would be valuable is the ability for the user to import their own database of games to use for the move tree – this would allow the user to make their own choice  (for example using only games played between players above 2500 elo etc) – sadly Chess Openings Pro doesn’t give the user this option either.

The Pro version (but not Lite) helpfully includes an engine to provide analysis in positions where there isCOE_engine_output no tree available. This is a valuable feature allowing for independent study particularly in less popular lines, where for example the opening tree may run out of games only a few moves in. The user can play the opening against the engine or use it to analyse specific positions. The engine analysis is clear and includes all key information such as evaluation, suggested move and optimal line of play (principal variation). It’s not all good news though as there are a number of niggles that if resolved would increase the app’s practical use. For example:

  • there’s no option to set or influence the analysis time  – a best move will be suggested or played at a certain fixed 12 ply depth  (analysis will however continue beyond this if play option is disabled as in the image above)
  • there is no multi-pv option available, which is an important  feature for analysis purposes (multi-pv allows an engine to analyse and display more than one move at a time – for example the best two or three moves in the current position). This is helpful for example when trying to assess the merits of different possible moves
  • the engine used isn’t identified so it is difficult for the user to gauge the quality of the analysis and how much reliance to place on it


The app has a range of additional learning features which are of varying practical use. Probably the most significant of these is the quiz mode where the user can test their openings knowledge by answering a range of multiple choice questions. These can be selected based on your own preferred openings (which can be saved separately) or randomly generated.

The quiz mode is a fun and potentially useful exercise  and a % score is awarded at the end of the test. However, some of the answers and comments appear rather contrived and/or inappropriate – for example it makes little sense to tell me I have chosen the least popular move if all 5 moves available have only been reached in a total of 7 games! In reality,  I suspect the real benefit to this option will lie in testing yourself against your own preferred openings rather than the classic quiz which throws an apparently random assortment of openign positions at you.

There is also an Opening of the Day option, which on selection presents what appears to be a random opening position with associated database analysis. And that’s about it. In short it’s not clear what the point of this specific option is other than perhaps to introduce users to new openings.

Taken together it is likely these features could leave the user with a rather dissatisfied feeling  – whilst it may be interesting to see a broad range of opening positions and also be useful to develop some broad awareness – the reality is I’m not likely to be playing or facing many of these openings. I suspect the average player will be wanting to develop an in-depth knowledge of a much narrower range of openings. For example,  if I only play d4 and have the caro-kann as my defence of choice as black to e4 then I’m not interested in the complexities of the Sicilian or Ruy Lopez. Of course the opposite could be argued also and the app may be useful in stimulating the user to find and try out new, perhaps even ‘offbeat’ openings and variations.

Practical use and presentation

The app is well designed and easy to use. All options are clearly identified and accessible from a single screen. Additionally, the app’s chess engine can easily be engaged at any point by a simple swipe. The developer has clearly given useability some thought and this is shown in several small but nice touches. This includes for example use of a small coloured pawn to clearly indicate which side the engine thinks is ahead and an ‘Opening Book’ option  which allows the user to access and set up the board with any opening and variation however obscure, at the touch of a button.

Visually the app is appealing having a clean and uncluttered appearance. The chessboard and pieces are clear and easy to view – no awkward colour clashes of garish colours. The only slight disappointment is that there is no ability to alter the default options to add some variety.

Developer support

Chess Openings Pro is an app that is in active development with a history of regular releases. Updates have provided bug fixes and improved functionality. The developer is available via an email address which is readily available either from the app store or within the app itself. Whilst easy to use, the app also has an element of built in support, via a simple help button, which covers the basic operation of the app.



  • Simple to use
  • Good visual presentation
  • Large database of games
  • Inclusion of chess engine for self-analysis


  • Inability to import/load alternative database
  • Engine used is not identified
  • Opening of the Day seems a bit pointless


There are some additional more detailed notes about this app in the Developer notes section.

These are my thoughts; if you have used this app what do you think…..





Chess Openings Explorer

chess openings explorerReview details:
App version: 1.10.1
Device:  Samsung S4 Mini
Operating system: 4.4.2


A useful tool for the casual player wanting to improve their opening play but the serious user and stronger player is likely to be disappointed

Chess Openings Explorer is a free android app developed by Anton Duzenko which is free to download and notably also free from any advertising

The app is an analysis tool which enables  chess openings to be studied in two ways by using:

  • information from a database of opening moves which is drawn from the results of a large pool of games;
  • an integrated chess engine to provide detailed analysis of specific positions and the option to play out games from openings of the user’ choice.

A database of moves with associated frequencies of wins/draws/losses is a commonly used format in established chess database applications. The Openings Explorer uses the normal approach of displaying the results in a ‘tree’ of the individual moves from the current board position. This is an effective approach as it enables the user to quickly see which are the most frequently played moves from a given position and what the also which produces the best results.


The underlying database is perhaps the most important feature of an app dedicated to chess openings analysis. Such an app lives or dies by the quality of the games the database uses; so how does Explorer do in this area? Let’s take a look…

COEThe database of games is literally massive – using 2.3 million games played on the Free internet Chess Server (FICS). This means that the database is large enough to provide a sufficient coverage of openings to a reasonable depth – it also means that (other things being equal) results are more meaningful – in reviewing a potential move I would be more comfortable with the conclusions from 100 games than say 10. The quantity of games certainly allows trends to be identified and enables different moves to be more easily compared.

However, the database size is not all good news; it brings both practical and usability drawbacks:

The vast number of games means that the app size is huge – the developer recommends at least 770Mb of free space  – so if your device doesn’t have external memory the app may well be a ‘no-no’ to start with. Additionally, the developer also indicates there are potential problems regarding external storage for non-Samsung users

There is a trade off between quantity and quality. The larger the pool of games used the lower the average quality of the games will be. Put simply, there won’t be 2.3 million games from Magnus Carlsen or Gary Kasparov. As an example, in my own games database of over 4 million games –  only some 60,000 were played by players who both had ratings of over 2600 (ie Super-GM). The reality is that many of the FICS games are of very low quality. They are often at blitz time controls between weak players with many poor moves. This obviously impacts on the reliability of the assessments of individual opening moves COE_Grobwithin the app. As an illustration, there are at least 30 games of the following:

1 – g4 e5
2 – f3 or f4

Of course, this is a terrible opening in it’s own right leading to the quickest possible loss by checkmate – what is worse is that of these 30 games only twice was the immediately winning move 2..Qh4++ played! Equally, it is not hard to find opening moves which drop whole pieces. So, the app isn’t likely to inspire the confidence of the serious openings student or stronger player. However, for the casual or weaker player the quality of the games arguably doesn’t matter so much as they are far more likely to be facing non-optimal moves in the games they play.

The other big disappointment regarding the database lies in the fact that there is no option to change it and load in your own games database. This inflexibility means that you can’t rectify any of the quality issues identified above nor for example use a specific subset of games to practice a particular opening in-depth (eg import a database of solely Budapest Gambit games between Master strength players).

There is however good news with the inclusion of a chess engine which can be used to play and analysis openings which can be used to play a full game. The engine  ‘Cuckhoo Chess‘ by the respected programmer Peter Österlund, whilst not being of top strength is still a good one. It feels appropriate and well-matched to the app given the type of player it is likely to appeal to and sufficient for the needs of the user.

Practical use and presentation

COE_menuThe app is relatively simple and easy to use. There are few options and those that are available are easily accessible from a single menu bar. These are practical including the ability ot rotate the board, return to the start position or use the engine

Entering moves is straightforward, simply by tapping the relevant board squares which are highlighted for clarity and there is a back button to return to the previous position.

Visually, the app looks attractive. Although there are no means to alter the chess board or piece type, the options selected are well chosen and make for pleasant viewing. The evaluations for individual moves for the side to move are shown using separate percentages for win (displayed in green) and losses (in red) together with the number of games where that move was played.

Whilst the user experience is generally positive, it must be noted that the app does lack a COE Settingslittle polish. The purpose of the app’s settings are not immediately obvious (none are explained) and indeed on discovery several appear rather pointless (‘Hide ActionBar’ – why would the user want a title bar displaying the app name taking up screen room anyway!?). There are a few more detailed specific comments regarding use and presentation on the developer page.

Developer support

The app has been actively developed with regular updates, the current version dates from June 2015. The app appears well supported. The developer invites feedback and has responded to user feedback left at the Play Store which is always a good sign. It is also clear that user comments have been addressed in subsequent releases.

Whilst it is not a complex app and users of other chess opening apps will no doubt be familiar with the app’s layout and approach, the absence of any simple instructions on the Play Store page or within the app itself is an omission that should be corrected to help beginners and new users.



  • Free and ad-free
  • Large database of games
  • Inclusion of good chess engine for self-analysis


  • Size of games database sacrifices quality
  • Inability to import/load alternative database
  • Settings are not explained and add little benefit


These are my thoughts; if you have used this app what do you think…..

Opening Tree

Opening treeReview details:                                                                           
App version:  1.2
Device:  Ipod Touch 4th ed
Operating system: ios 6.1.6


A potentially useful tool for learning about chess openings but rather limited and let down by a small database. Design and layout makes use on a mobile device difficult.

Opening Tree is a free app from Michael Adams who is responsible for a range of chess related apps and software. It is also available for the Ipad and includes an inapp purchase giving the user added features, in this case the ability to edit, score moves and make notes. This review is of the free version (ie without the additional purchase option).


Opening Tree is an analysis tool which enables you to study chess openings in two ways, using either:

  1. information from a database of opening moves which itself is drawn from the results of a large pool of games; or
  2. a chess engine to provide detailed analysis of specific positions

Opening tree_3The database of moves with associated frequencies of wins/draws/losses is very helpful and is a commonly used format in established chess database applications. It enables the user to quickly see which are the most frequent moves from a given position and also which produces the best results. As a small improvement, in addition to W/D/L information the % score for each move would also be helpful to more clearly identify the relative success of each move.

The quality of the database of opening moves used is crucial for this to be a useful tool for analysis. In this regard the Opening Tree app is somewhat disappointing. The size of the database used is relatively small, (due to memory constraints on the ipod?). This means that it doesn’t take very many moves, even in the more popular openings before there are either no more or too few results to be meaningful. As an example, if you want to study the Budapest Gambit (1 d4 Nf6 2 c4 e5) you’ll find the database has the results of just 33 games after only the 2nd move. The other drawback is that there is no information included within the app to help assess the quality of the games used to build the database. For example, games where both players are rated above say 2500 elo might be considered a better reference source than where the minimum rating was 2000 elo.

The inclusion of a chess engine to provide analysis of potential moves is Opening tree analysisalso a good feature. This enables the user to check and assess possible opening lines and counter moves. The chess engine included with the app is Crafty 23.4 – a longstanding and well-respected engine, which happens to be one of my favourites. Whilst Crafty is certainly strong enough for this purpose for the average app user, I can’t help thinking that most knowledgeable users would prefer one or more of the top strength engines that are freely available (for example Stockfish) for analysis purposes. Sadly, Crafty is not one of these.

There are additional analyis features. An in app purchase allows you to assess and record particular moves by using different colours to signify good and bad moves and you are also able to make notes about speciifc moves. The review didn’t test this functionality.

However, it is after a while of using the app that some of the weaknesses with the concept begin to become apparent. Yes, it provides a good way of reviewing and assessing opening lines but it is rather limited in how this can be achieved. The app has a lack of accompanying features that would be helpful for studying purposes. For example, the app doesn’t actually let you play or practice any opening  – the engine is only available as an analysis tool and not a playing partner.

Learning and user edited work on opening lines can’t be exported for use in other apps, nor can the learning be utilised in any other practical way by the app. For example, the app doesn’t allow the user to generate an opening book from their research to use either in the app or another alternative program or app. So there is no direct way to use the app to play against or test your own research and pet lines, you will need to fire up and another chess app.

The user can import their own PGN files of games into the app either via email or ITunes file sharing. However, due to technical constraints (essentially catering for the needs of older devices) only small files of no more than 500 games can be handled. On the Ipod once a PGN file is loaded it is a terribly fiddly and frustrating job to ‘step’ through the moves of a game to be able to compare them to the database. This is down to the size of the controls more of which below. I found myself veering between stepping forward and backwards too often for comfort.

In summary, in considering the combination of features and flexibility I was left with the feeling that a dedicated chess database app might not be a better option.

Practical use and presentation

Opening tree_mainThe first thing that’s obvious when using this app on a mobile device is how small the chessboard is. The board takes up just over half of the screen size and means that not only is it potentially difficult to view but that the dreaded ‘fat finger’ problem is likely to come into play. The result is that if you want to enter moves manually (rather than via tapping the particular move from the movelist) the size of the individual squares makes it tricky to tap the correct piece. There feels to be areas of wasted space on either side of the board (maybe the arrow keys could be located here?) and there is no option for resizing the board. Neither is there any potential for screen rotation, and I wonder if landscape format would be better at least on an ipod (this is available on the iPad version).

These issues combine to leave a feeling that the design of the screen layout for the ipod/iphone user at least, could be better.Opening tree_options

However, although size and layout can’t be altered, there are opportunities for tailoring the presentation. Within the ‘Settings’ option there are a range of easily accessible options for changing various visual aspects. These include a good range of different chessboard colours, background colours and at least two chess piece sets. Refreshingly (unlike some other apps) the choices are between well-designed and respected piece sets which are both very clear and comfortable to use.

Developer support

The app description on the ITunes store is failry descriptive in terms of the app’s features and operation. This is supplemented by some specific notes of instruction on selecting relevant options; in particular when loading a pgn file for the first time. The developer has also included a change-log on his website together with contact details for support.

To date the app has had only one update since its original release, this being a year since the writing of this review. As such it doesn’t appear to be in active development. However, the author has released and/or updated other chess apps in the intervening period, so it is too early to conclude that the app is dead.



  • Free and ad-free
  • Inclusion of chess engine for self-analysis
  • Good choice of visual options
  • Simple and easy to use


  • Chessboard is too small to view/use comfortably
  • Small size of database of opening moves
  • Uses a relatively ‘weak’ chess engine
  • No recent updates


These are my thoughts; if you have used this app what do you think…..?