Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: Can I just connect via bluetooth and play music without using the Sony App?
Document: You definitely need the manual to decode display options such as "C.AUD+", "DSEE", "AAV", "RB ENH", etc.In terms of device support, the unit works at SOME level with ANY Bluetooth-enabled phone or tablet - I can for instance play music or use the handsfree with myancient Nokia phone. However it is primarily intended for use with the "Sony App Remote" application, which is only available for Android and iOS.
So if my kids are playing an audiobook from their tablet in the back seat through this receiver, I will not see any visual status indicators or other feedback at all. (That will instead be shown in the Sony App Remote screen on the connected tablet/device).Sound quality is not quite as clean and crisp as on my JVC unit - it appears a bit more "canned" (for lack of a better word).
Just got it installed. Pairing with my nexus 4 went without a hitch. Bluetooth audio quality was great. But it looks, for the lack of a better word, ugly. Im waiting for my xperia z ultra to be delivered to see if it improves the look. But i doubt the fit in the cradle will be snug for anything but an experia phone. This is just after 20 minutes of use. will update after I've gotten more use out of it.
I use Milk Music mostly since no ads. Google Maps works great, it will even read your texts to you when you get one. Sounds great. Tuner works fine. Settings work well. Price was nice too.
Largely it does what it needs to do. Using it with a Moto X at the moment. The USB charging connector is a bit clunky (connector is reversed if you snake the wire from the bottom), but that's fair -- there's no one solution for all the different connector placements that exist. Once connected and aligned with the app, it plays back from the tuner, or from any other apps you assign to the App Remote app.It's the little things though that can make this incredibly frustrating.
So needless to say, you get the most out of this unit when used with a Sony Xperia phone.NFC-enabled devices (even my Nokia) can pair with a single touch, otherwise manual pairing is needed. Once paired, the unit will remember your device even if other devices are paired in the meantime. Meaning, you can keep several devices paired - though I don't know (and the manual does not say) how many.
The only thing I've been able to make it do so far is run a preset app. Sort of. Google has an absolutely amazing voice control option with Google Now, but nope. Pressing that "Voice" button takes you to some crippled feature that should've stayed in the lab. You can still run Google Now voice commands manually through your phone though -- I guess you can add it as an "app".
When "App Remote" runs on connection to the unit, it seems to crash the main launcher (I use TFS, haven't tested with others yet). Hitting "Home" and going to the launcher seems to kill the app's connection to the unit. I've resigned to simply adding apps I'd need as shortcuts in the "App Remote" app and never going back to the launcher.
With the top and bottom piece and the phone in landscape, however, it's a bit of a pain to get a good swipe in. And if it's not quite a swipe, the phone recognizes it as a press, sending you into FM2 and requiring 4 more presses to cycle you back into FM1 where you started.Anyways, the silver lining here is that there are mostly software issues. Hopefully Sony will be willing to fix them (soon, if you're reading this Sony =)).
The remote app needs improvements.
Answer: Yes. I have to do this because the app doesn't work with the latest version of Android.