Default Android Phone as secondary display for another Android Phone


As the summer-time appears, I'm about to mod my 4wheeler, and I just found one of my old Android Phones (Htc EVO3D).
I thought about methods to build in ,my Android phone in my 4Wheeler and use this as an Display for my android phone.
I'm thinking of a VNC-Server and a VNC-Client. But also I thought about all the smartwatches and Co.

In my opinion it should be doable to use one of those Android-Roms and port them to my Phone.

Did anyone of you thought about this, or know a other way to reach my goal ?

Maybee you can help me.

If you like my work buy me some sweets ^^ ... I don't like coffee

Huawei Ascend P6 - AOSPA 4.4.4
HTC Evo 3D - CM10.2 4.3.1 3.0.101-MiRaGe

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