[Android General] ixian:
Sure. I set up two profiles, one for HDMI Plugged, one for Unplugged. I then set up a task for each, I called them Car Connect and Car Disconnect.

Note: I have an N5 with 4.4 which means I need to bounce the BT connection. Also Screen Standby doesn't work with it right so I removed that.

Apps I used in this config:

GravityBox/Xposed Framework: This is a nice framework/plugin for "stock" devices that are rooted - it gives you a lot of features that custom ROMs have like statusbar tweaks, quick select, etc. I use it for a lot of things but what's relevent here is GravityBox allows you to A) Configure what kind of Expanded Desktop you want (full on or remove buttons and keep statusbar, which is what I use) and B) Now allows you to create a "shortcut" to toggle this.

Autoshortcut: This is a simple, free plugin for Tasker that allows you to configure Tasker to launch shortcuts. Why this isn't built in to Tasker I don't know, but it's simple enough to do. You'll need it to access the GravityBox Immersive Desktop mode toggle.

Taskkill: One of the better app-killers out there that more importantly has a plugin for Tasker, so it's super-easy to tell tasker to stop an app. Has several methods available, usually recommend to use "extreme" if available (this does the same thing as a force-close). I use this to stop Waze and other apps that like to sit running in the background when I don't need them. I also stop ARU this way because of my BT issues.

Car Home Ultra: It's 4 bucks (has a 30 day trial, it's free to get on the Play store). This is my favorite front end/launcher for cars - you can add your own app or other shortcuts, create music controls, add the weather/time, lots of good stuff. Easy to customize the colors, has a day/night mode, and can be configured to automatically start Car Mode - what this does depends on your phone (some phones, like the Moto X, will read your texts to you in car mode) but what's common across all is it will allow Car Home Ultra to temporally become the default "home" screen while Car Mode is active - this means when you use the home button on your AR it will take you back to Car Home Ultra, not your stock launcher. When you exit Car Mode (which I do with Tasker) it reverts to your regular launcher.

I can't say enough good things about Car Home Ultra, it really makes the whole day to day use of AR/ARU a breeze

Finally, there is ARU injector, sold by our very own Area51, which allows the HU GPS to work with apps that aren't using the Pioneer SDK. I recommend buying it to support this project even if you don't think you need it.

Here are my Tasker Tasks:

Car Connect:

Set BT off

Wait 2 seconds

Set BT on

Wait 5 seconds

Load App: ARU

Wait 5 seconds

Load App: Car Home Ultra

Wait 2 seconds

AutoShortcut: Configure to toggle GravityBox: ExpandedDesktop

I used to have Send Intent: Turn on Screen Standby which you can add at this point if it works for you.

ARU is also configured to rotate the screen to landscape on BT connect so I no longer have to use Rotation Locker (I used to have that in this task as well).

The entire process, starting from the point where I clear the nag screen warning on the AppRadio (if you are in the US you already know this will appear every time you start), takes 24 seconds. At that point I am looking at the main screen for Car Home Ultra and can start whatever apps I want from there, like Waze or Google Play Music.

Car Disconnect:

Wait 4 seconds

Taskkill ARU

Wait 2 seconds

Taskkill Car Home Ultra

Wait 2 seconds

Taskkill: Waze (if running)

Car Mode: Set off

Autoshortcut: Toggle GravityBox expanded desktop

Other than finding a "fix" (Pioneer or otherwise) to the BT issue - which as you can see really only adds a few seconds time with Tasker - the only real issue I have left is finding a reliable way to shut off my N5's screen while outputting over HDMI. The two apps I've tried so far don't work well with KitKat but hopefully that will change. I'm not worried so much about power savings, it's that I have a dock for my phone and having both screens on - the phones screen sideways - is distracting. But it's a minor nitpick in the scheme of things, as I don't know how to disable the screen in KitKat on my own anyway.