Just snagged two of these when they were up for sale last week, and I have to say that I’m actually pretty impressed by the sound from them. They produce a very good quality sound for the price, with much better bass than I had expected for a speaker of this size. I would definitely recommend getting at least 1 or 2 for this cheap.
I know, this is probably a stupid question… but can you connect one device (iPhone) to multiple bluetooth devices?
Yes: you can “PAIR” numerous devices, but you can only use ONE device at a time.
Meaning, once you “pair” the device(s), (i.e. hands free kit, speaker, head phone, etc.) you then go to the Apple Settings menu -> Bluetooth and select which device you would like to use. And that “specific” device will communicate with your iPhone.
FYI: these speakers do have a mic, so you can use them as a “hands free” device to take calls.
Unfortunately for me- I purchased two of these during the last Woot and both will not charge. I noticed some of the other “Wooters” reporting the same issue. 
For their size (and price), the sound was VERY good. I was pleasantly surprised.
I bought one of these from Woot about 6 months ago. It held up pretty well initially. And the reviews are correct, for such a small inexpensive unit, this thing has great sound. The issue is, the glue used to hold the speaker in the cradle isn’t very robust and failed about 6 months in. I used this little guy in my disc golf back (nerd alert-I know) so I was walking around with it a lot. So maybe it is a good choice for someone looking for minimalist office desk sound or otherwise stationary use.
Do these play music while charging (via USB cable)?
i bought two of these and the sound is decent but the charging port is not assembled properly. They will not charge. NOT WORTH PURCHASING.
You get what you pay for! Not significantly different that sound quality or volume from Samsung smartphone. Package and manual to not list the manufacturer or contact information…so good luck!