This presentation by "Katzenmann" provides a comprehensive overview of PostmarketOS, a mainline Linux distribution for smartphones, positioning it as an open and hackable alternative to the increasingly restrictive Android and iOS ecosystems. The talk explains the technical foundation of PostmarketOS, which involves replacing the Android kernel with the mainline Linux kernel and rewriting drivers for device-specific hardware by reverse-engineering existing code.
The speaker candidly discusses the current state of usability. While core functionalities like calls, mobile data, Wi-Fi, and GPS work well on supported devices, significant limitations remain. These include the inability to receive calls during deep sleep (suspend), a lack of push notifications, and poor camera quality due to missing post-processing and autofocus drivers. Despite these issues, the battery life is surprisingly good, and the main appeal lies in the complete control, freedom to tinker, and the ability to run familiar Linux desktop applications. The presentation concludes by outlining the project's future challenges, emphasizing the critical need for broader device support, improved hardware drivers, more mobile-optimized applications, and the implementation of Voice over LTE (VoLTE) as 2G networks are phased out.
PostmarketOS: Running Mainline Linux on Your Smartphone
0:45 Motivation for Linux on Mobile: The speaker presents PostmarketOS as a liberating alternative to the increasingly closed-source and restrictive nature of Android and iOS, offering more freedom for users who want to tinker with their devices.
1:48 How PostmarketOS Works: It replaces the device's original Android kernel with the mainline Linux kernel. This requires significant effort to write new, clean drivers for hardware components (display, camera, audio, etc.), often by reverse-engineering the complex and poorly documented Android drivers.
4:32 Current Functionality: On well-supported devices like the Pixel 3A, essential features such as calls, mobile data, Bluetooth, Wi-Fi, and GPS are functional. It's also possible to run Android apps, but this requires significant RAM as it runs a full Android stack in the background.
5:27 Key Limitations and Issues: The platform is not yet fully mature. Major drawbacks include the inability to receive calls when the phone is in deep sleep (suspend), the absence of a push notification system, and UI scaling issues where many desktop apps don't adapt correctly to the small screen.
6:53 Surprisingly Good Battery Life: Contrary to the reputation of early Linux phones, modern PostmarketOS installations can achieve excellent battery life. The speaker shows an example with over 11 hours of runtime remaining at 43% battery, provided background processes are managed properly.
10:05 Poor Camera Quality: The camera is a major weak point. Images suffer from a lack of post-processing and autofocus because the necessary drivers have not yet been written for many devices. This results in blurry and discolored photos.
10:45 The Main Appeal: Freedom and Control: The primary reason to use PostmarketOS is the complete control it gives the user over their hardware and software. It allows for running custom scripts, interfacing with other hardware, and using the same applications across both desktop and mobile.
16:35 The VoLTE Challenge: A critical hurdle for the future is implementing Voice over LTE (VoLTE). Currently, calls primarily rely on the 2G network, which is being phased out. Developing VoLTE is difficult due to proprietary, manufacturer-specific implementations that must be reverse-engineered.
18:53 Installation Process: To install PostmarketOS, one must first check for a supported device, then download a pre-built image or use the pmbootstrap tool to create a custom one, and finally flash it to the phone.
23:16 Recommended Hardware for Newcomers: The speaker advises against using new phones, which can take years to get good support. Instead, he recommends buying a well-supported used device like the OnePlus 6T, which has a strong community and good performance.
25:58 Outlook for Mainstream Adoption: The speaker estimates that it may take until 2030 before PostmarketOS is polished and reliable enough for the average, non-technical user.