The development of the live version of SMath seems to be stalled. Besides, now the program is oriented to integrating plugins developed by the community, which brings me to the question, would it be possible to make these external plugins compatible with the SMath webservice ?

Hi, this free framework could be useful for the SMath live version. If I understood right it is a C/C++ framework which outputs for android, ios and html5.
http://www.mosync.com/

Answering the initial question (yeah, I know, it was 1 year ago ): yes, development is continued now and we have really better web-application now.

Regards.