Website of Dmitriy Dotsenko: Best dictionary application (big update 5)

The best dictionary program is GoldenDict for Android

Features:

Support for ABBYY Lingvo .LSD, .DSL, .LSA and .DAT files (including user dictionaries), StarDict files, Babylon .BGL files, Lingoes .LD2 files, Dictd files
Rich formatting in dictionary articles, including images and sounds
Support for Hunspell morphologies
The program will understand your typing no matter how you do it - forget about diacritics, case or punctuation

Best dictionary software for desktop computer:

1st place) GoldenDict for Windows

www.goldendict.org
Download the latest version: https://github.com/goldendict/goldendict/wiki/Early-Access-Builds-for-Windows

Open-source cost-free dictionary software. Includes only dictionary shell, dictionaries are not provided but can be found on other websites. The software can read dictionaries of several formats: .dsl (not-yet-compiled text dictionary for ABBYY Lingvo or illegally decompiled .lsd dictionary of ABBYY Lingvo), Babylon, StarDict, DictD, Sdict, Aard (aar-html), xdxf. So, more than 4 000 dictionaries for tens of languages can be used with this software, including English into Russian dictionaries (e.g. Multitran English-into-Russian dictionary of 2 December 2011 - 2,605,007 entries), Russian into English dictionaries (e.g. Multitran Russian-into-English dictionary of 2 December 2011 - 3,082,662 entries), Russian into Russian explanatory dictionaries (e.g. Russian Wikipedia without pictures of July 2007, Big Soviet Encyclopedia and Big Encyclopedic Dictionary) and English into English explanatory dictionaries. GoldenDict can also look up words in online dictionaries, such as Wikipedia, Wiktionary, Multitran.

Almost all existing dictionaries:

www.lingvodics.com (in Russian; almost all dictionaries existing in Lingvo formats)
www.forum.ru-board.com/topic.cgi?forum=5&bm=1&topic=30250 (in Russian; some other dictionaries in other formats)

Features:

Freeware
Open source
Rich formatting in articles (transcriptions, stress, colors, links, pictures)
Look up words in online dictionaries (such as Wikipedia, Wiktionary, Multitran, bab.la)
Spelling suggestions when incorrectly typing word for look-up
No need to switch languages and directions of translation
Interface in English
The program will understand your typing no matter how you do it - forget about diacritics, case or punctuation
List of dictionaries in which a word was found
Unicode support (dictionaries for any language)
Working with several articles simultaneously (tabs)
Buttons "Back" and "Forward"
Groups of dictionaries (for example, English-Russian, English, Russian, English grammar)
Can be portable
Change the order of dictionaries
History of lookups
Create own dictionaries (using other software)
Select a word in another application, press a keyboard shortcut (for example, Ctrl+C+C) and see translation in the main window opened
Press a keyboard shortcut, move the cursor over a word (in different programs, even menu titles, button titles but not words on pictures) to see the main window open with translation

Wanted features / problems:

- Decompiler of Lingvo x5 system dictionaries into .dsl (now GoldenDict cannot use dictionaries of Lingvo x5)
- GoldenDict does not understand .ann files of annotations for .dsl dictionaries, therefore it is impossible to find out information about a dictionary from the program
- It takes very long for the list of dictionaries in the panel on the right to appear if online dictionaries are also checked (because the list appears when everything is fully loaded). So, one has to use the old method of opening context menu with the list of dictionaries where the word was found. This list is available at once. The suggestion is to display offline dictionaries fast and a rotating disk for online dictionaries meaning that they are being checked. When they are available, to show them too.
- Own dictionaries of the software (one for each language direction)
They shall be stored online. The software shall be able to download needed online dictionaries and then automatically update downloaded dictionaries from the internet regularly (like Multitran)
- Users shall be able to add individual words into own dictionaries of the software (like Multitran)
- Users shall be able to correct translations of own dictionaries of the software (like Multitran)
- Users shall be able to import their own dictionaries (in a special format) into own dictionaries of the software. Only those words shall be imported which are absent in own dictionaries of the software (Multitran partially has such feature, users just send their dictionaries to the author of Multitran to be added in the dictionary)
- Users shall be able to specify topic of the word when adding translations into own dictionaries of the software (like multitran.ru)
- Users shall be able to specify part of speech of the word when adding translations into own dictionaries of the software (like multitran.ru)
- Users shall be able to suggest topic of the word when adding translations into own dictionaries of the software (like multitran.ru)
- Users shall be able to specify Notes (link to source, explanation) when adding translations into own dictionaries of the software (like multitran.ru)
- When looking up a word in Wikipedia links must be preserved to other language versions of the same article.
- When looking up a word in online Multitran, it must be possible to add a word using interface of online Multitran.
- Program for converting Anki deck to dictionary (this would allow using Anki as program for creating dictionaries for the software)
- Optical text recognition (to look up a word under cursor if it is on a picture)
- Infected forms of a word (like ABBYY Lingvo)
- Full text search (like ABBYY Lingvo)
- Wildcard search using ? and * (like ABBYY Lingvo)
- A website where users would be able to suggest features and vote for them, such as www.uservoice.com. See an example on www.anki.uservoice.com. Then developers of the program will know what features are most needed (popular) among users. When a user is trying to add a new feature, the website shows to him already existing similar features to avoid duplicates. The service is cost-free. Now users of GoldenDict have to use forum of the software to suggest features, but it is difficult to check whether somebody has already suggested such feature. And after a feature is added, it gets hidden behind new topics and new users cannot comment on it.
- Good forum with possibility to subscribe to all updates (as forum of Anki which is a Google group). There you can subscribe to all updates and receive an email every day with all new topics and topics that received new replies.
- When a word is being looked up, the frame on the right with the list of dictionaries where the word was found still shows the list of dictionaries where the word of the previous request was found. New list of dictionaries appears only after all information from online dictionaries is loaded.
- When I want to see translation in a certain dictionary, I click on this dictionary in the bar on the right with the list of dictionaries in which the word was found. After I do this text in the main frame (where dictionaries entries are shown) scrolls up (slider goes down) to this dictionary heading and the heading is placed on the top of the frame.
But if I click on the last dictionary in the list, its heading is placed not on the top of the frame with entries because there is no enough empty space under word entry of the last dictionary to put its heading on the top of the frame.
This issue is not a big deal but it is inconvenient to expect to see the dictionary heading on the top but to find it somewhere at the bottom.
- Highlighting heading of the selected dictionary in the main frame (where dictionary entries are shown).

2nd place) ABBYY Lingvo
www.lingvo.ru

Best dictionary software for smartphone:

1st place) GoldenDict for Android (see the beginning of the post)

2nd place) ABBYY Lingvo x3 for Windows Mobile

iOs
There are no really good dictionary programs for iOS. The best dictionary program is Lingvo for iOS but it does not support user dictionaries.

Best collaborative online dictionaries:

1st place) www.multitran.ru
2nd place) www.wikipedia.org
3rd place) www.glosbe.com
www.glosbe.com
Started in September 2011.

Features:

Translations, definitions
Any languages supported
Dictionaries for very many languages are available
You can choose any language pair
Easily switch between your preferred languages
When looking up a word, you will see concepts with translations and definitions
Screen keyboard for special characters of the active language
User interface in many languages
Free of charge
Dictionaries include not only dictionary entries but also translation units (translation memory)
Units of translation memory are shown apart from dictionary entries
You can email your own dictionary or translation memory to the website owners
Biggest translation memory provider, hundreds of millions of translations in about 2000 languages, thousands of bilingual dictionaries, hundreds of thousands of pronunciation recordings, millions of concepts
Add your translations
Add definitions to translations
Definitions in any languages
Translations into various languages can be connected to a meaning (building a concept-based dictionary)
Vertical list of translations which are near the active translation in the dictionary
See definitions of a concept in various languages and its translations into many languages
Delete a meaning associated with a concept
See recent changes for a dictionary
See the number of words in any dictionary (you need to look up a word in a dictionary, then to click <> on the left panel to change direction of translation, then to click it again to go back to needed direction; then you will see information about the dictionary)
See new words in a dictionary (you need to look up a word in a dictionary, then to click <> on the left panel to change direction of translation, then to click it again to go back to needed direction; then you will see 2 tabs with information about the dictionary; the 2nd one will be "Recent changes")
Add synonyms (you need to associate translations with a concept)
When a user is looking up a word, all phrases with that word are also found and placed separately
Description of the format in which users should upload dictionaries is available on the website
Added information can immediately appear in search results

May not work:

Interface for uploading your translation memory: http://glosbe.com/upload-tm
Interface for uploading your dictionary: http://glosbe.com/upload-dict
Delete a translation associated with a concept
Users are notified when their dictionaries are uploaded

Wanted features:

Bidirectional dictionaries (for instance, Russian-English dictionary is monodirectional)
Bigger dictionaries (so far dictionaries are much smaller than on www.multitran.ru)
Possibility to download dictionaries
Possibility to translate from one language into several (as on www.deect.com)
Specify part of speech and topic when adding translations
Mark a mistake in a dictionary entry
Delete (or suggest to delete) a translation (or a definition)
Case-insensitive search
If 2 translations of a word have the same definition (they are synonyms), they both should be displayed near each other within the same concept when translating the word
To group concepts by part of speech (not to mix parts of speech in results)
If a user cannot find a translation and does not know it, he can ask for it in a forum on the same website
When somebody suggests a translation for a word requested in the forum, it is automatically added to dictionary
Users can add any languages
Users can subscribe by email to new topics on interested for them language division of the forum
Users can subscribe by email to new messages in interesting for them forum topic
When looking through search results, the user can click translations which suit him better; they appear on top of results; after looking through all results, the user goes up to his best results and choose the best one by doubleclicking on it. If a translation was onceclicked, its position in the results goes up 1 level, if a translation was doubleclicked, its position in the results goes up 2 levels. Then best concepts will be on top and worst in the bottom of a part of speech. Within a concept the best translation will be the first and the worst - the last.
When looking up a word, the user sees all found concepts grouped by parts of speech. If he thinks that he should look up translation in a topic, he clicks a found topic on a separate panel. Then he sees not all found concepts but only found concepts within the topic.
Found phrases with the word should be grouped by topic (because usually there are many of them)
Users can see and download all concepts of a topic
When adding a translation, the user should be able to add translations for not only 2 but for any number of languages selecting them from drop-down list

Less good collaborative online dictionaries: www.langtolang.com, www.dict.cc, www.wiktionary.org, www.logos.it, www.bab.la, www.hablaa.com

Good but not collaborative online dictionaries:

www.deect.com

Features: