[GUIDE] Android Device as Screen for rPi via USB & VNC

[Mikagami]

My Problem: I like to travel lite when going abroad and a rPi doesn't add much weight. but screens or monitors do and I always have my phone or a tablet with me.

Goal: Be able to use my android device as the head of my raspberry pi.

I researched high and low and tried different solutions that have worked for other people but for some reason or another it didn't for me. So after finally finding a solution for my problem I decided to post it in case it helps someone else. Now I used an android device but any device that you can install a VNC client on and connect it to the rPi via USB should work.

Physical Materials I Used:
1: Raspberry Pi B
2: 16GB memory card
3: Android Device (Nexus 5)
4: Standard Cables & Adapters (micro usb, power adapter for pi, hdmi to vga, keyboard & mouse)

Software Used:
1: Raspbian Jessie ver. Nov 2015
2: SD Formatter
3: Win32DiskImager
4: x11vnc (for the Pi)
5: bVNC Free (for the Android Device)

Step 1: Install Raspbian to SD card

The rPi Foundation has already created a great guide to install Raspbian so here are their resources:

Download Raspbian Image: https://www.raspberrypi.org/downloads/raspbian/

Install Image to SD Card: https://www.raspberrypi.org/documentation/installation/

Step 2: Configure Standard Settings on rPi

Once again the rPi Foundation has great documentation for this as well.

Configure rPi: https://www.raspberrypi.org/documentati ... -config.md

*Note that all I did was expand the file system and set the localisation settings, nothing else.

Step 3: Configure USB port with a static IP

This piece of the guide is thanks to Joshua Woehlke's post, with a little change:
http://joshuawoehlke.com/android-raspbe ... -over-usb/

Log into the rPi and get to a terminal window either via SSH if already using the Pi headless, starting the GUI by typing

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startx

, or if you are already at the terminal window then...great.

We will configure a USB interface to have a static IP, which we will later use to connect to the rPi from our android device. To do so type the following and press enter:

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sudo nano /etc/network/interfaces

Add the following code somewhere at the end since you will have interface data there already:

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allow-hotplug usb0
auto usb0
iface usb0 inet static
address 192.168.42.42
netmask 255.255.255.0
network 192.168.42.0
broadcast 192.168.42.255

Once done entering that data press "control+X", on the next prompt press "Y" then finalize saving the data by pressing "Enter".

Step 4: Install x11vnc on the rPi

This piece of the guide is thanks to a post by "emg" in the following thread on the forums:
viewtopic.php?p=108862#p108862

To install x11vnc type the following and press enter:

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sudo apt-get install x11vnc

Next lets set a password that we will need when trying to connect to the rPi with our android device later. Type the following and press enter, you will then be given the option to type your desired password:

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x11vnc -storepasswd

Step 5: Create an autostart entry for x11vnc

This piece of the guide is from the same post referenced in Step 4.

We need to have the vnc server run automatically when we give power to the rPi so that all we really need is to connect our android device. To do so type the following lines of code and press "Enter" after each line.
First Line:

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cd .config

Second Line:

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mkdir autostart

Third Line:

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cd autostart

Fourth Line:

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nano x11vnc.desktop

Now insert the following text:

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[Desktop Entry]
Encoding=UTF-8
Type=Application
Name=X11VNC
Comment=
Exec=x11vnc -forever -usepw -display :0 -ultrafilexfer
StartupNotify=false
Terminal=false
Hidden=false

Once done entering that data press "control+X", on the next prompt press "Y" then finalize saving the data by pressing "Enter".

Step 6: Install VNC client on Android Device

Go to the Play Store and install the free app bVNC:
https://play.google.com/store/apps/deta ... bVNC&hl=en

Shutdown the rPi, DON'T JUST UNPLUG IT, connect your android device to the rPi using a USB cable, make sure no other usb devices are connected to the pi and you can unplug video source (monitor, tv, whatever you were using to configure the Pi).

Power up your rPi and wait about 20-30 seconds for it to boot.

Turn on "USB Tethering" on your Android device. On Android Marshmallow I had to go to "Settings", "More", and "Tethering & portable hotspot" to find the setting.

Open the bVNC app and enter the following IP in the "VNC Server" field:

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192.168.42.42

Enter the password you set back in Step 4 into the "VNC Password" field and click the "Connect" button.

If everything went smoothly then you should now see the GUI interface for Raspbian.

Now you can use your android device to control your rPi!

[Seafood]

You have no idea how much I needed that

[karrika]

Thanks for sharing. I have to try this tonight.

[Mikagami]

I am glad this has been of help to others.

I really enjoyed this setup since the rPi now gets internet from my phone and I get to control the rPi via a touchscreen, pretty handy.

[blaablaaguy]

Do you need internet access on the phone/to do this?

[BMS Doug]

Do you need internet access on the phone/to do this?

You'll find it hard to install the software without it.

Once installed the pi communicates with the phone by USB so internet isn't necessary.

[dosnoventa]

I keep getting an error when trying to connect through the vnc:

"java.net.ConnectException: failed to connect to /192.168.42.42 (port 5901): connect failed: EHOSTUNREACH (no route to host)"

i keep trying to find the source to this issue and i followed every step accurately, i even did it twice and it still wont work

[DougieLawson]

Is VNC display :1 (port 5901) running? Is that the right address for your RPi?

[DougieLawson]

Check it with sudo netstat -tlnp | grep vnc

Please reply on the forum, DO NOT send private messages.

[dosnoventa]

Check it with sudo netstat -tlnp | grep vnc

Please reply on the forum, DO NOT send private messages.

i checked and the port 5900 is listening, but even if i use that port on the vnc viewer, i still get the error message

[DougieLawson]

What task is listening on 5900? What happens if you explicitly start vncserver :1 from a command line (or LXTerminal)?

[dosnoventa]

What task is listening on 5900? What happens if you explicitly start vncserver :1 from a command line (or LXTerminal)?

The task listening on 5900 is x11vnc and i tried starting the vnc server explicitly and nothing happened, unless i missed something, but it shows x11vnc listening on port 5900

[DougieLawson]

Is 192.168.42.42 really the address of your RPi? What's the IP address of your Android tablet? Is it in the same subnet?

[Mikagami]

Do you have your device connected to the correct interface? USB0 in the guide. Try a different port if you are unsure.

I apologize if it seems simplistic but just making sure all rocks are being turned.

[thintin]

Hi.

Thanks for this tutorial, it's really easy to follow and was a great help. I am having one problem though...



...any suggestions?

This is the screenshot from my Xperia Z4 tablet which has a 10" 2K screen. I tried using my older Jellybean 7" tablet (which is what I really wanted to use) but USB tethering isn't available on JB unless you have a data connection, and this old tablet only has WiFi!

[Meeeric1]

Hello. I have e tried doing this using the first method and did everything, but when I clicked "connect" on the bvnc app, I got an error message saying:
"Connection failed Connection to VNC server failed with reason : Server did not offer supported security type . Please ensure you have picked the right item in Connection Type java.lang.Exception : Server did not offer supported security type Please ensure you have picked the right item in Connection Type . at com .iiordanov . freebvNC.RfbProto.s electSecurityTypeAfbProto.java : 627 at com.iiordanov.freebvNC.RfbProto.n egotiateSecurity ( RfbProtojava : 514 ) com . ii ordanov . freebvN C. RfbProto.i niti alizeAndAuthenticate ( RfbProtoj ava : 382 ) at com . ¡ iordanov . freebVNC . RemoteCa nvasstartVncConnection ( RemoteC anvas - java : 429 )"
What does this mean, and what should I do?

[danoz]

works great by now I have a probelm:
the WIFI isn't working...
how can I make the WIFI work while controlling the pi via USB??

thanks

[dongleason]

The tablet wifi or the Pi wifi?

[danoz]

pi wifi

[dongleason]

Go take a look at forum # 168507 (static ip for usb in Raspian Jessie). It solved my problem and hopefully it will fix yours too!

[danoz]

thnak you

so you have the RP's wifi working, while connected to your phone via USB?

[danoz]

Go take a look at forum # 168507 (static ip for usb in Raspian Jessie). It solved my problem and hopefully it will fix yours too!

hi,
tried this but the RP's WIFI is still not working...

[AzraelEcho]

Go take a look at forum # 168507 (static ip for usb in Raspian Jessie). It solved my problem and hopefully it will fix yours too!

hi,
tried this but the RP's WIFI is still not working...

Hi,

I met the same problem and solved it. I guessed that the key is how to set the static IP for usb0. As in forum # 168507, there are two ways.

The first one (maybe the popular one) is to amend the sudo nano /etc/network/interfaces file with:
allow-hotplug usb0
iface usb0 inet static
address 192.168.42.42
netmask 255.255.255.0
network 192.168.42.0
broadcast 192.168.42.255
gateway 192.168.42.41

For me, the usb0 works but I met the problem on the usb wifi adaptor. I cannot find the wlan0 and eth0 in ifconfig.

Then I tried the second one, by amending the sudo nano /etc/dhcpcd.conf file with:
interface usb0
static ip_address=192.168.42.42/24 (I used 192.168.42.214 as suggested in https://raspberrypi.stackexchange.com/q ... -a-network)

Both the usb0 and wlan0 work.

Hope it is useful.

P.S: If anyone knows what's the difference between amending /etc/network/interfaces and /etc/dhcpcd.conf, please tell me. Someone suggested not modify the first one (viewtopic.php?t=191453)

[LEDDIM]

If you add your Android phone's hotspot to your Pi's wifi networks you can directly connect your phobe's VNC viewer to the Pi. I use it as a backup, in case I change to another network I can use my phone'sVNC viewer to connect to my Pi and set up a new wifi connection.
You can also connect other devices to your hotspot and use VNC viewer from there.No internet connection (4G) required...

[gilius]

Great guide.

FYI: that "USB Tethering" is easily confused with "USB Tethering" under default connection mode (previously known as RNDIS prior to Android 9), but the option we need is actually under hotspot settings instead.