Make a Mobile Phone UI for a Raspberry Pi

People love their phones. So, if you can have the user interface (UI) of your Maker project be their phone, do it. It also makes your project less expensive and with less parts to troubleshoot and maintain. This guide takes you through setting up the Pi as an ad hoc Wi Fi module so one can connecct. It then provides a simple web server example to serve as the interface.

-Raising Awesome ©2021

One thing to note - Windows 10 no longer will connect to ad hoc networks. Don't know why they chose to stop, but they don't. It has something to do with new drivers for wifi. If you need to access the Pi terminal while in ad hoc mode, I use an iPhone app called Pi Helper to connect.

Step 1: Make a backup of your Pi's existing wifi profile:

sudo cp interfaces backup-interface

Step 2: Create an ad hoc interface

sudo nano adhoc-interface

Step 3: Paste this into the file

auto wlan0
iface wlan0 inet static
wireless-channel 4
wireless-essid MyPiAdHoc
wireless-mode ad-hoc
wireless-key YOURPASSWORD
Hold Ctrl+X, then tap Y and enter to save it.

Step 4: Install a DHCP Server

sudo apt-get install isc-dhcp-server
Press Y if prompted to do so. This will take a minute to install.

Step 5: Create a DHCPD Config File:

sudo nano /etc/dhcp/dhcpd.conf
ddns-update-style interim;
default-lease-time 600;
max-lease-time 7200;
log-facility local7;
subnet netmask {

Step 6: Set the Pi to Use the Ad Hoc Interface Profile

sudo cp /etc/network/adhoc-interface /etc/network/interfaces
Note: to set it back to your profile from step 1, do this:
sudo cp /etc/network/backup-interface /etc/network/interfaces

Step 7: Get My Example Web Server

cd ~
git clone

Step 8: Set the Webserver to Run at Startup

crontab -e
Then put this in the file and save with CTRL-X:
@reboot python3 /home/pi/CardReader/

Step 9: Reboot and Connect with your phone!

Enter in your phone's browser to connect to your webserver interface.