Kiwix

Kiwix (No Internet - No Problem!) - a useful application containing a ton of web sites with information, for android devices.

An irreplaceable assistant in the learning process
Kiwix (No Internet - no problem!) - useful and sometimes irreplaceable an application for the learning process and even just to expand the horizons, thanks to which all the content from the popular Wikipedia, including thematic selections, Wiktionary, speeches on the TED, as well as information from more than a hundred cognitive websites, including documentation from Ubuntu, WikiLeaks, WikiSource will be downloaded to your android device.

Access to information without an Internet connection
Everything you have to do for comfortable work with Kiwix (No Internet - no problem!) Is a one-time download of the information you are interested in from the proposed websites and be able to use them anywhere and anytime without connecting to the Internet. Files can be quite large and weighty, so it is important to prepare free space on your android device and try to download information only from the sections of interest so as not to overload your smartphone.