How do I open a text file of any extension in Android? I have several types of file on my Google Drive and on my SD card (.C, .ASM, .H, .INC, .LOG) which are all just text files. But I just can't view them on my Android phone because it says that there are no programs assigned to that file type. Dropbox would do fine if I could just assign it to open these extensions. So, my questions are:


Is there a way to assign any extension I want to Dropbox?
Is there a text viewer that will let me do that?


I tried so many, but none seem to do it. Only this HEX editor https://play.google.com/store/apps/details?id=tuba.tools seem to do it, but it won't allow me to view as a text file. Only in a split HEX/TEXT screen.
A programming editor might solve your issue. Take a look at e.g. 920 Text Editor or DroidEdit:

 
920 Text Editor and DroidEdit (Source: Google Play; click images for larger variants)

Both support at least syntax highlighting for several programming languages, and from the screenshot at least DroidEdit seems to be able to directly work with Dropbox (see the headline).