Export .obj file with png texture I'm playing around with Google's new Augmented Reality SDK. 
Their example project contains an .obj file but its' textures are not in a .mtl file, put a .png file; no .mlt file at all (example for an Android robot model below). 

From a little research I take this is not the 'standard' procedure of exporting a model / it's texture in the .obj format from Blender (or similar programs). 

Is there a way to still achieve this (textures in .png instead of .mtl) with Blender?
The .mtl file is only a material definition file which contains references to textures.

if you want to export obj with .mtl and textures you need to make sure you follow these steps:

In your OBJ export menu:


Make sure material export is ticked





Set the path mode on COPY




You will see that in your target folder you now have


An obj file which contains your mesh information
An mtl file which contains material definition
All tetxure files referenced in the .mtl