[Android General] ixian:
The popular one on XDA seems to be the MK809 III, but it gets a lot of flak for weak wifi. There are some other suggestions in this thread somewhere.

The trick is, you'll need to do some stuff with your phone anyway because you're probably going to want wi-fi tethering - even if right now you think you don't. Tasker or another automation app will make the process of auto-connecting tethering, etc a lot easier. I do a lot of internet streaming in the car via Pandora and Spotify myself, plus it's just easier to have for app updates, etc.

There's also boot time to think about since even if you hard wire the power it's going to have to cold boot every time you start your car and I don't know how long those sticks take to boot - if it's as long as a phone that could get annoying.

Overall it's not a bad idea in theory, but I've read about a lot of mixed results with this approach. You'll also probably want the ARU Injector, since no stick I know of has built in GPS (if you hide it away it would mostly likely be useless anyway). Apps such as Waze and Navfree that use the Pioneer SDK will use the HU GPS anyway, but everything else that needs GPS will need the injector.

I've found by using Tasker to automate things based on whether I am connected to HDMI and my Car BT can save you the extra expense and trouble - the way I have it set now, my phone flips in to modes appropriate for a car when I connect and flips back when it isn't, so it's no big deal (though it took some doing to set up at first). The issue for me now is figuring out my Proclip car dock so I can easily pop my phone in and out - no one makes a nice car dock that works with SlimPort/MHL, for built in docks they all provide regular 4-pin micro-usb for charging only. It's the one and only thing that I miss from my old iPhone 5 setup since there is a dock that works with the lightning connector - I didn't have to attach my cable every time, it just popped in and out. Getting that to work for my Nexus 5 is going to take some doing and probably a little modding with a dremel.

I've looked in to USB sticks too but so far I haven't seen much reason to go to the trouble (and expense) over just using my phone. Everyone's situation is different though so if you try it let us know.

---------- Post added at 10:48 PM ---------- Previous post was at 10:39 PM ----------

Edit: I found a video of a guy using an MK809 III with an AppRadio 3 - he speaks in Russian (and is wearing a wifebeater, which is somewhat hilarious) but you get the idea.

http://www.youtube.com/watch?v=NJ4uROduGz4

One thing I noticed off the bat is from the time he powers on the MK809 it's 50 seconds before it boots and the home screen shows up - and from that point you have to launch ARU, etc. So even if you automate the process you are looking at a full minute, easy, each time you start your car - and that's not counting the time it takes for the AppRadio itself to start so you can clear the nag screen.

With my N5, even counting the time it takes me to manually hook up the SlimPort cable it's less than half that before I am up and going, CarHome Ultra loaded and everything. Granted, that's because my phone is already on, but that's normally the situation so.... I dunno, I like the idea, but that is a pretty slow boot for a process that will happen every time you turn your ignition on.

Edit again: I guess - I have read about this - you could always hook it to an always on power source, considering there's no display and you can use tasker to turn wifi, etc on and off it probably doesn't draw all that much power, but I could easily see it killing your car battery if you don't drive every single day. Seems like a lot of trouble.