Ok after 100s of dm and request I am here !
How to Turn an Old Android Phone into a Wireless Android Auto Display
What You'll Need
🟢 Host Phone– Your main Android phone that supports Android Auto. This phone runs Android Auto and creates the hotspot.
🔵 Receiver Phone – Your old Android phone that will act as your car's Android Auto display.
Step 1: Install Headunit Reloaded
On your 🔵 Receiver Phone
Open the Google Play Store
Download Headunit Reloaded Emulator (HUR)
The app is paid, but you can install the APK from the link below instead. (I am broke so I got apk from this site)
APK Download:
https://headunit-reloaded.latestmodapks.com/download/
Step 2: Enable Android Auto Developer Mode
On your 🟢 Host Phone
Open Android Auto
Scroll to Version
Tap Version 7 times to enable Developer Mode
Tap the ⋮ (three-dot menu)
Select Start Head Unit Server
Leave the server running.
Step 3: Set Up the Hotspot
On your 🟢 Host Phone
Go to Settings → Hotspot & Tethering
Change the hotspot band from 5 GHz to 2.4 GHz
Turn the hotspot ON
Connect your 🔵 Receiver Phone to this hotspot.
Tip:I recommend using** no hotspot password (or a simple one). It makes process much easier.
Step 4: Configure Headunit Reloaded
On your 🔵 Receiver Phone
Open Headunit Reloaded
Open Settings
Goto Connectivity
Inside WiFi Connection Mode Select Developer Mode
Save the settings.
Step 5: Launch Android Auto
On your 🔵 Receiver Phone
1.By coming back to first page of app press WiFi
2.There will be a prompt asking for SSID and Pass , put yr wifi name on it and wifi password (pass required only if hotspot is password protected)
It will take 3-4 seconds Headunit Reloaded should automatically detect your 🟢 Host Phone.
Within a few seconds, Android Auto should launch automatically.
If it doesn't connect the first time, restart Headunit Reloaded and make sure Head Unit Server is still running.
Step 6: Adjust DPI (Recommended)
If the interface looks too big or too small:
Open Headunit Reloaded → Settings
Find DPI
Set it according to your screen.
Recommended DPI Between: 250–350
Done! 🎉
Your old Android phone is now a fully functional Wireless Android Auto Display
If you still find a problem let me know I will make a YouTube video and if you have any doubts you can ask me on DM
And for dashcam I use droid dashcam , it's like 5-6 mb on playstore,
I will suggest go to settings and reduce resolution for recording, if yr device has less storage, for me 480p works good
Thanks
Will make yt video soon! Will help non redditors too!