How to use an old Android phone as an OctoPrint server for 3D printers

You can install OctoPrint on a Raspberry Pi with a camera module to track your prints and create amazing time-lapse videos. But what if you don't have a Raspberry Pi?

Here, TipsMake will explain how you can install and set up OctoPrint on your old smartphone. You can use any old Android device to install an unofficial version of the OctoPrint server, automatically create time-lapse videos of your prints, and monitor prints remotely.

Steps to set up and run OctoPrint server on Android

To control your 3D printer with OctoPrint on your Android smartphone, you need to install the Octo4a Android app. This is an unofficial application developed by FeelFreeLinux on GitHub.

With the Octo4a app on your Android smartphone, you can install OctoPrint on your Android device and use it as a host. It works just like OctoPrint on Raspberry Pi, also supports SSH, allows you to log in to SSH to manage, update, and customize your OctoPrint installation on Android. The steps are as follows:

Step 1: Gather the necessary things

You will need an Android smartphone running Android 4.3 or higher. It doesn't matter how long the machine has been in use. If the phone still turns on, you can use it for this project. Also of note, the app seems unstable with newer versions of Android, such as Android 12.

In testing, the app crashed when using the Galaxy S20+ running Android 12.

You will also need a USB hub or OTG adapter. This is important because OctoPrint consumes significant power when tracking and recording time-lapse videos.

Find a small tripod or any attachment that can hold your smartphone in place to shoot time-lapse videos from a certain angle. You can also design and 3D print a case or stand to hold your smartphone.

Step 2: Download and install the Android Octo4a app

The Octo4a Android app is not available on the Play Store. However, you can download Octo4a.apk from its GitHub project page.

To get the app, you can use the ADB command or just download the app, tap Install > Settings to trust the source, then tap Install again.

Wait for the installation to finish.

Step 3: Install and set up OctoPrint on an Android smartphone

After installing the Octo4a application, you can open it, grant the necessary permissions and click Continue. This will start downloading and installing the required dependencies and files. Based on your Android device and Internet speed, this may take up to 30 minutes to complete.

After your phone completes the installation, you can tap it to start the OctoPrint server on your Android device. Alternatively, go to Settings and enable the camera to stream video for real-time tracking and time-lapse creation.

You can also choose the camera resolution and frame rate (FPS). Depending on your device, you can set the FPS to 30 FPS. Keeping the frame rate lower will save battery life and avoid overusing or overheating the device.

Go back to Home and click Start OctoPrint server. This process may take a minute to start. Once started, you will see an IP address.

Open a web browser on your PC and go to the IP address shown in the app, such as 192.168.xx.xxx:5000.

Now, follow the wizard to set up the OctoPrint server. In this wizard, you will create an account with a password and edit the 3D printer details, such as bed size, nozzle width, etc.

Once setup is complete, you're ready to connect your Android device running the OctoPrint server to your 3D printer for remote control and monitoring.

Step 4: Connect the 3D printer to your Android smartphone

To connect your 3D printer to your Android device, you will need a cable or an OTG adapter. You can buy a cheap OTG hub or cable from Amazon or a retailer near you. This will allow you to keep your device running 24x7 without worrying about the battery.

Connect the USB cable from the printer to your smartphone using the OTG adapter. Then, connect the smartphone charger to the other end of the OTG cable or power input port. If your Android phone has a USB-C port, you can purchase a USB dongle with multiple ports to connect a printer and power source.

On your Android phone, give the app permission to access the USB serial port.

The 3D printer is now connected to the Octo4A app.

On the web interface in the browser, click Connect. Wait for the server to automatically find and connect to your 3D printer.

Once connected, you can try to move the axis or click the Home icon in the Control tab to make the move automatically. This will help you ensure that OctoPrint is connected and able to control the printer.

You can upload GCode to the SD card connected to your 3D printer, select the GCode already on the SD card and click Print to start 3D printing.

In the timelapse preferences, you can edit the settings to automatically record a basic timelapse video when printing begins.

Alternatively, you can go to Settings > Plugin Manager and install the Octolapse plugin to create amazing timelapse videos. The videos are stored in your Android device and can be downloaded once finished.

Similarly, there are several other plugins that you can install in the OctoPrint server hosted on your Android device to add additional features and functionality.