Look around: touch screen and slide finger
double tap: place a node or use selected item
long tap: dig node
touch shown buttons: press button
Buttons: ** left upper corner: chat ** right lower corner: jump ** right lower corner: crouch ** left lower corner: walk/step... left up right down ** left lower corner: display inventory

When a menu or inventory is displayed:

double tap outside menu area: close menu
tap on an item stack: select that stack
tap on an empty slot: if you selected a stack already, that stack is placed here
drag and drop: touch stack and hold finger down, move the stack to another slot, tap another finger while keeping first finger on screen --> places a single item from dragged stack into current (first touched) slot

Special settings

There are some settings especially useful for Android users. MultiCraft's config file can usually be found at /sdcard/Android/data/mobi.MultiCraft/files.

gui_scaling: this is a user-specified scaling factor for the GUI- In case main menu is too big or small on your device, try changing this value.

Requirements

In order to build, your PC has to be set up to build MultiCraft in the usual manner (see the regular MultiCraft documentation for how to get this done). In addition to what is required for MultiCraft in general, you will need the following software packages. The version number in parenthesis denotes the version that was tested at the time this README was drafted; newer/older versions may or may not work.

android SDK (28+)
android NDK (r17c)
wget
g++-multilib
m4
gettext

Additionally, you'll need to have an Internet connection available on the build system, as the Android build will download some source packages.

Build

Debug build:

Enter "build/android" subdirectory
Execute "make"
Answer the questions about where SDK and NDK are located on your filesystem
Wait for build to finish

After the build is finished, the resulting apk can be fond in build/android/bin/. It will be called MultiCraft-debug.apk

Release build:

In order to make a release build you'll have to have a keystore setup to sign the resulting apk package. How this is done is not part of this README. There are different tutorials on the web explaining how to do it
- choose one yourself.
Once your keystore is setup, enter build/android subdirectory and create a new file "ant.properties" there. Add following lines to that file:

key.store= key.alias=MultiCraft
Execute "make release"
Enter your keystore as well as your Mintest key password once asked. Be careful it's shown on console in clear text!
The result can be found at "bin/MultiCraft-release.apk"

Other things that may be nice to know

The environment for Android development tools is saved within Android build build folder. If you want direct access to it do:

make envpaths . and_env

After you've done this you'll have your path and path variables set correct to use adb and all other Android development tools
You can build a single dependency by calling make and the dependency's name, e.g.:

make irrlicht
You can completely cleanup a dependency by calling make and the "clean" target, e.g.:

make clean_irrlicht

The new build system MultiCraft Android is still WIP, but it is fully functional and is designed to speed up and simplify the work, as well as adding the possibility of cross-platform build. The Makefile is no longer used and will be removed in future releases. Use the "Start" script, which will automatically load pre-assembled dependencies, prepare localization files and archive all necessary files. Then you can use "./gradlew assemblerelease" or "./graldew assembledebug" from the command line or use Android Studio and click the build button.

When using gradlew, the newest NDK will be downloaded and installed automatically. Or you can create a local.properties file and specify sdk.dir and ndk.dir yourself. The script will automatically create an APK for all the architectures specified in build.gradle.