Anyone know where is I can get tutorial for Boundless Web App Builder with QGIS for Open Geo Suite? (in video or pdf format).
I had tried to search on Google, and tutorial mostly for ArcGIS.
I guess you are referring to the Boundless Web App Builder?
There is a Tutorial right from the source: Building Openlayers3 WebApp
They also have a whole section of tutorials:
If you prefer PDF over a HTML based documentary you can build it with Sphinx - the complete documentation (and information about the build process) can be found on their Github repository.