Getting started with Android


Cumulus is a well established Open Source flight navigation software made for (but not limited to) soaring pilots written in C++. The primary hardware targets were Sharp's Zaurus devices and later Nokia's Internet tablets. Both are able to run Qt software with relatively little adaptation efforts which made it possible to use large parts of the desktop flight preparation software KFlog, created for the KDE framework. The Android Lighthouse project provides a development kit, called Necessitas, for integrating Qt C++ applications into the Android environment with little or no changes, embedded in as native libraries controlled by the JNI API (Java Native Interface).


Package download and installation

The last released package is to find on Google play as Cumulus from Download the package and install it on your device.

Permissions required by Cumulus

Cumulus requires the following Android system permissions:

First startup of Cumulus

On the first startup of Cumulus after the installation you should have an Internet connection running to download the needed maps and the Welt2000 data file. Cumulus ask you for permission before it starts any download actions.

It is recommended to setup the font sizes of the GUI and the Menu labels to a value, which is optimal adapted to your device. To do that, open the menu item General and touch the entry Look&Feel in the list. On the page you can see two buttons, which will open a font dialog, if you press them. Choose a font size, which is optimal adapted to your device. Make only small changes and test the results. To get full running a new selected font, it is recommended to restart Cumulus. Especially the Menu font should be adapted by you, that it is better usable with fingers.

Configuration of Cumulus

As first you should setup your home data and the radius around it. To do it, make the following actions:

The maps and all other data as waypoint files, IGC logger files, flight task file, a.s.o are stored at the SD-card of the Android device. If your device has already a built in SD-card, this one is normally used. To see, which SD-card is used by Cumulus, press the Android Menu button, then Setup->General, Personal. Beside the label Data Directory the path to the storage directory is listed. You can access this directory also from your PC, if you couple your device with it via USB.

Airspace files have to be installed in /sdcard/Cumulus/maps/airspaces. The path /sdcard/... can be another in dependency of the used Android release. If that is true, please read the previous paragraph. You can download the airspace files by using your Internet browser and as destination that directory. On the airspace setting page you can determine which airspace files should be loaded during run-time by Cumulus. In Cumulus you can use OpenAir and openAIP airspace files.

Links where you can find OpenAir airspace data are:

OpenAir airspace files must be installed manually in the required directory. Download and installation are not supported by Cumulus.

openAIP airspace files can be downloaded and installed by Cumulus in its airspace configuration settings.

GPS activation

When Cumulus is ready with its startup, it will be in a non-GPS mode. Do all your flight planning work in this mode. To switch on the GPS, press the Android menu button and select the entry GPS on. You can choose then between the internal GPS or a GPS connected via Bluetooth or via a USB IOIO. A BT GPS must be paired before it can be used by Cumulus. Only via Bluetooth radio or USB IOIO you can connect to an external GPS device.

Menu usage

Cumulus has two different menus. The Android menu can be opened by pressing the Android menu button. It provides some shortcuts to the important setup pages of Cumulus and the GPS switch to control the mode. To show the application menu, touch the Menu or the S2f field at the bottom of the value display area on the left side. Touching the little boxes left of the map can open additional dialogs for configuration or toggle the display to show another content. Here are a short list about all:

Usage note

The native Qt GUI part has some restrictions in its usage. Therefore some GUI elements, e.g. color dialog, are not optimal to operate.

Cumulus provides an online help. Please have a look into it, if you have questions about the usage. The Online Help is also to find on the Cumulus web page in two languages, in English and German.


If you step in problems and need further help, please contact the Cumulus team via email at We will help you in every case, if we can.

Remarks to Android

A big problem is the variety of OS releases and that the manufacturers can modify the Android OS provided by Google. That can cause additional problems during run-time and makes a testing not more possible by us on every device and for every OS release. Also the native Qt GUI library port for Android is not yet error free.

Have fun during flying with Cumulus! That are my (Axel Pauli's) personal wishes to you. I'm the maintainer of Cumulus.

And something more, if you like the App, please tell a friend from it and don't forget to vote for it on Google Play!

Author: Axel Pauli,     9. October 2014