The eLog library was initially developed as a research prototype and later published for lifelogging researchers in 2010 to help them easily analyze heterogenous data and complex visualization. It has been kept growing with the progress of mobile computing environments and recently its UI part is released with GPL v3 license for wider usage. The eLog UI library is optimized for mobile environment and can get easily integrated with existing Web services.

Who We Are

The original work was proposed by Pil Ho and later extended the work with collaboration with 28 researchers around the world who contributed their lifelogs, collaborated for lifelog analysis and share research results to build up an open lifelogging platform for the public. Pil Ho has been keeping the development updating the library following up the progress in mobile computing.


  • Nov. 2014: Change the web page skin using bootstrap.
  • Nov. 2014: Published elog UI library as GPL v3.
  • Oct. 2014: Version up eLog library and documentation.


Tips for students

Let me summarize a number of tips for students to help you more:

  • PLEASE read Tutorial and before reading it, please log-in to test APIs with your own API key.
  • Your API key is not your db name or site user id. It is the md5 hash of a string looking like '1f3870be274f6c49b3e31a0c6728957f'. You MUST log in to get your API key at https://www.elifelog.org/book/elifelog-api
  • If you think that your API key is not working or elifelog.org site is down, please try our e-Log interace (https://www.elifelog.org/article/e-log-interface) first. If it shows all data correctly, then our back-end system and the site is working fine with your API key. If your e-Log interface is not working, then please report to me by email.
  • Now GetImage API supports UNIX timestamp based retrieval, which is time zone independent. This would be useful when setting local time zone is confusing. See https://www.elifelog.org/book/elifelog-api for examples.
  • When writing a SQL statement, use a standard English font. It is especially important when putting a single or double quotation mark into the query. Font size should not be a problem and in fact don't work with a rich editor like MS-Word when writing a SQL query. Rather use a 'notepad' like editor or work directly on MySQL client software. They will not automatically convert user inputs like quotation marks that MySQL can not recognize.
  • When running a statement with time_zone settings (ex SET time_zone = "+2:00"; SELECT blahblah), DO not use phpMyAdmin like Web clients since it chops off them into separate statements that loses the time_zone setting effect on following statements. Also, Web clients may encode special characters (ex. quotation marks) into something else. So if you are not that familar with these background knowledge, stick to MySQL client software that runs on your OS system and run two statements at one query to be effective for time zone changing without glitches.