If you want to use the Android app but cannot download chosen topics via the internet you may download any topics here and manually copy them to your phone or tablet.
TopicsTopics
Download Topics Manually (not recommended)
DOWNLOAD LINKS
HOW TO MANUALLY INSTALL TOPICS TO ANDROID

- Install and run the Nature app on your phone.  Exit when you see the download topics page. The 'Aviasoft' folder is now created.

- Download the chosen topic file. Unzip it (it has a topic folder inside).

- Move the topic folder (not the zip) within the 'Aviasoft' folder on your device's internal memory.  Now run the app, tab the back button to get to the menu and tap 'TOPIC' to choose your topic.

Aviasoft folder is at:  internal memory/Aviasoft/'your-topics-here'/

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