Halna Outliner is a free outline processor for Android developed by halna. It features a two-pane interface with one pane for the tree part and one for the notes part. The app offers three different display styles, including vertical, horizontal, and switch. Additionally, it can be used in cooperation with the idea mapping app 'HalnaMind'. Halna Outliner supports import from WZmemo, Natara Bonsai CSV, OPML, and TreePad(TM), while export is possible in text file, WZmemo, OPML, and TreePad(TM) formats.

Halna Outliner is a useful tool for those who need to organize their thoughts and ideas. Its two-pane interface makes it easy to navigate and work with different parts of your outline. The app's compatibility with other software, such as HalnaMind, allows for even more flexibility in brainstorming and planning. Overall, Halna Outliner is a solid choice for anyone in need of an efficient and user-friendly outline processor for their Android device.