How to use an Android device as Raspberry Pi touch screen display?

Last Updated on September 11, 2023 by pg@petergamma.org

Why to use tablet PCs or smartphones with a big screen as Raspberry Pi displays?

• smartphone or tablet pcs with touch sreens with the same or better resolution than Raspberry Pi displays can be found cheap on eBay.
• Tablet PCs and smartphone offer a buil-in battery.
• They offer a power management which is strongly optimized. The power management of Raspberry Pis is rather basic and offers only view power saving options, which is an issue for mobile use.

So why not to use a tablet PC or as smartphone as a Raspberry Pi toch screen display? Tech Craft showed us how to use a iPad Pro with usb-c connector as a mobile Raspberry Pi 4 touch screen:

He has used this setup for two years and is very happy with it. The advantages are:

• it requires only a usb-c cable connection to a RPi4 which is fast.

• the usb-c cable of this setup can be connected to a hub for additional connectivity such as charging while while using it.

But it is difficult to find iPad Pros with usb-c connectors on eBay. We have to check every offer with every version if it support usb-c or not. So why not to use a tablet PC or an Android phone instead of an iPad pro with usb-c? iPad Pro with usb-c which meets the requirements to be used for a cable connection to a Pi to be used as a monitors currently cost between 200 to 300 USD on eBay.

• iPad Pros which meet the required usb-c standard which is described in the start from gen 3. 2018:

https://www.gsmarena.com/apple_ipad_pro_12_9_(2018)-9387.php

• There are other iPad Pros with other screen sizes and other specifications which is confusing for us personally.

Android tablets with usb-c and similar specifications than these iPad Pros can be found between 100 to 150 USD in eBay.

For us personally an issue is that we do not know of an example who to connect a Android tablet PC or smartphone to Raspberry Pi 4 over usb-c cable and SSH to an Android table. But it is possible. Tech Craft shows this at 7:04 in the above video with the iPad solution.

We do not know of an example which uses the connection method shown in the video for Android. It goes over SSH. An issue of Android devices is according to Tech Craft furthermore that he could not find a solution how to charge an Android device at the same time as he uses it with the Pi.

But there also Android tablets available such as the

Lenovo Tab P11 which offers a Smart Charging Station

It can be charged over a connector on the bottom of the tablet which does not require the usb-c connector, which is then free to connect to a Pi even during charging.

But as long as no example for an SSH cable connection is available for Android to connect it to a Pi we have found another example which uses a WIFI hotspot and a VNC viewer on an Android device:

WIFI is not optimal for mobile applications. But we can use this example for a remote desktop for a Pi controlled by an Android phone or an Android Tablet as the Lenovo Tab P11 over WIFI instead of over cable.