I am thinking about buying a smartphone while in Tokyo.
Do you have any physical store (I leave on Monday morning) to recommend?
I've already been to Yodobashi, where they showed me about 15 models.
( YodObashi, not YodAbashi )
Yodobashi would be my first choice, unless you want an iPhone. Bic is more-or-less the same as Yodobashi, just the music is more annoying.
If you know which model you want, Amazon.co.jp is another good choice.
Do check that it explicitly says "unlocked" on the box. The Japanese mobile carriers generally do everything possible to keep you from taking your money elsewhere.
The reason I said "unless you want an iPhone" is service. Android phones are cheap enough that if it breaks after you leave Japan it's not worth fixing. iPhones start at US$600. Get them from the Apple online store, which also gets you worldwide warranty service.
Neither Bic nor Yodobashi want to see you again if you have problems with your purchase.