I'm pretty sure I tried this—I think the prompts were even in English, if I'm remembering correctly. However, I gave up after several tries of it looking for a taxi and not finding one while I was standing in the rain on a dark street corner. It would sit and look for minutes and appeared to be a broken feature.

I ended up taking a BRT line to get back to my hotel and it was great. All of my experiences with transit in Beijing were excellent. I just wish taxis or car services were an option for tourists.