Thanks, that would work indeed.
Or I could rig two microB cable ends together... (would need to ground pin 4 on the host side also). That feels like a hack, but using two cables feels "wrong" as well...
However, after reading up on the documentation/specification of the standard, officially, only microA plug <--> A socket are official USB-OTG connectors, and appliances which can act as either host or device ought to have a microAB socket (which is compatible with both microA -- for OTG, and micro B -- for chargind, or being used as a device (e.g. when connected to a computer as host). So strictly speaking, all the phones with microB port (and these are the only ones I know) are non-standard-compliant, as are the (therefore required) microBplug<-->Asocket connectors?
Or did I miss something?