In-app purchases
Content rating
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image
Screenshot image

About this app

Alpus is a viewer application for dictionaries in StarDict, DSL, XDXF, Dictd, and TSV/Plain formats ¹.


• Fast and fully offline operation
• Searches ignoring case, diacritics, and punctuation
• Wildcard search
• Fuzzy search
• Full-text search
• In-page popup translator
• History and bookmarks
• Customization options


Alpus is compatible with the following dictionary/file types:

• StarDict dictionaries (*.idx)
• DSL dictionaries (*.dsl)
• XDXF dictionaries (*.xdxf)
• Dictd dictionaries (*.index)
• TSV/Plain dictionaries (*.txt, *.dic)
• Hunspell dictionaries (*.aff)

Setting up dictionaries:

• Connect your mobile device to your computer.
• Copy dictionary files to the app's documents/files folder on device ². See Android help ³ for details.
• Select the dictionary index file as listed in the compatibility section above (or an archive of it) using the "Import Dictionary" option of the "Manage" menu.
• Select multiple indexes/files, with each selection assumed and analyzed as one dictionary. (optional)
• Select resource ZIP files (if any) to copy during importing. (optional)
• Edit properties of the dictionary such as visible name using the "Edit Properties" option of the dictionary menu. (optional)
• Create a full-text search index of the dictionary using the "Upgrade" option of the dictionary menu. (optional)
• Create profiles to group and organize dictionaries. (optional)

Resource files:

Resource files of a dictionary can be put into multiple ZIP files with arbitrary sizes and file names. The resource ZIP files placed into the root folder of a dictionary (beside Main.props file) will be detected and indexed automatically.

Full-text search:

The app supports searching full-text of all dictionaries for exact matches. The feature requires a one-time upgrading ("Upgrade All" option of the "Manage" menu) of a dictionary which can take a very long time to complete, since every single word anywhere on the dictionary is made searchable during the process.

Synchronizing between devices:

Copying/moving dictionaries between devices is done using one of the two available methods:

• "Export Dictionary" to an *.aaf file on the first device and then "Import Dictionary" that *.aaf file on the second
• Copy/move whole "Alpus.Config" folder or individual dictionary folders using a file manager or built-in file operations

Search types:

There are five kinds of searches you can perform on dictionaries.

• Regular search: Shows results exactly matching the query.
• Extended matching search: Shows results matching the query with case, diacritics, and punctuations ignored. Suggestions include in-phrase and phonetic matches.
• Full-text search: Shows list of articles containing exact matches of the query. The scope of search is not limited to headwords and includes all text in all articles (definitions, synonyms, examples, etc).
• Fuzzy search: Shows list of articles most similar to the query. The search works like a spell checker for words you're not sure how it's written/spelled.
• Wildcard search: Shows list of articles that match the criteria set with a wildcard query.

Help and Support:


¹ No dictionaries are bundled with the application. You will need dictionaries in supported formats to use with the application.
² Typical location of the app's documents folder is: Android/data/
Updated on
Jul 21, 2023

Data safety

Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
No data shared with third parties
Learn more about how developers declare sharing
No data collected
Learn more about how developers declare collection

What's new

• Bug fixes and performance improvements