PinePhone: trying out a Linux-based smartphone

The PinePhone is a Linux-based smartphone made by PINE64 that runs free and open-source software (FOSS); it is designed to use a close-to-mainline Linux kernel. While many smartphones already use the Linux kernel as part of Android, few run distributions that are actually similar to those used on desktops and laptops. The PinePhone is different, however; it provides an experience that is much closer to normal desktop Linux, though it probably cannot completely replace a full-featured smartphone—at least yet.

Goals

For several years, the only major options in the smartphone market have been Android and iOS. Android is an open-source operating system, but virtually all Android devices come with significant amounts of proprietary code; iOS is almost completely proprietary. Many Android phones and all iPhones have locked bootloaders, preventing the user from replacing the operating system.

Many phones are also carrier-locked, preventing the user from switching cell carriers without the approval of the one through which they purchased the phone. Few devices give the user root access without making modifications to the software and possibly voiding the warranty in the process. Overall, while the purchaser may legally own the device, in many ways it remains in the control of the manufacturer and often the carrier. Previous attempts at developing open-source smartphones have either failed or produced expensive devices.

PINE64 has been making various FOSS-friendly electronic devices for several years. The company originally made single-board computers (SBCs), and later developed devices such as laptops and tablets. One of its most popular devices, however, is the PinePhone, which is designed to promote mobile Linux distributions as an alternative to Android and iOS. The phone allows the user to install any compatible operating system, and it is not locked to a particular carrier. Instead, it is designed to give the user as much control as possible.

Distributions

Many distributions are available for the PinePhone, including DanctNIX (an unofficial spin of Arch Linux Arm for PINE64 phones and tablets), Manjaro Arm Mobile, Mobian (Debian for phones), postmarketOS (based on Alpine Linux), and Ubuntu Touch. Some of these, such as postmarketOS and Ubuntu Touch, were originally designed to be installed as custom ROMs on Android smartphones; others were developed specifically for the PinePhone and other Linux phones. All of these distributions, with the exception of Ubuntu Touch, are basically desktop Linux distributions with custom "desktop" environments designed for phones. (Ubuntu Touch is different in several ways, including a read-only root filesystem.)

There are also several mobile-friendly desktop environments available. The most popular are Phosh (similar to and partially based on GNOME, note that the Wikipedia article has more information than the project's sparse home page), KDE Plasma Mobile, and Sxmo (a minimalist environment based on a tiling window manager). Phosh and Plasma Mobile use Wayland, while Sxmo uses either X11 or Wayland. It is also possible to use regular desktop environments such as GNOME and Xfce, although they may not be usable with the phone's touchscreen.

So far, I have tested DanctNIX with Phosh. I still use my Android phone because of the PinePhone's limited app support and slow processor, but the user interface is usable and most of the basic phone features are present. Functions such as calling and texting work fine. MMS is supported, but most if not all distributions require the installation of extra FOSS components to use it. Once I installed the extra software and made some carrier-specific settings, MMS worked well, so group chats and sending pictures from the default Chatty app are possible.

Basic apps such as weather, calendar, and clock are also available, though alarms do not work if the phone is sleeping. I have not found an email client that works well, but webmail interfaces typically work fine in Firefox on the phone. YouTube worked well at 360p with occasional pauses on both WiFi and LTE in Firefox.

Pure Maps is an OpenStreetMap-based map app for Linux. I tried it briefly, and did not try to navigate with it, but the GPS worked. The interface seemed user-friendly, although it is written using Qt, so its interface did not match Phosh's GTK-based interface. Pure Maps is not available in the Arch Linux Arm repositories, so I had to use a Flatpak to install it.

Because Linux smartphones have a smaller ecosystem, there are far fewer apps available for Linux phones than for Android and iOS. Since iOS is a closed platform, it is not possible to run iOS apps on the PinePhone; however, Android's core is open source, making it feasible to run many Android apps on the PinePhone.

So far, three projects support this: GloDroid, Anbox, and Waydroid. GloDroid is an Android distribution that supports the PinePhone. Development seems to have stalled, however, and I did not test it. Anbox and Waydroid are compatibility layers for running Android apps on normal Linux distributions. They both work by running the Android user space in a container. Waydroid is the more popular choice, mainly because it has better performance than Anbox. Many apps, including some lightweight games, work well in Waydroid.

The only major issue I have noticed is that Waydroid does not support changing the screen size. If the phone is rotated, only part of the Android UI is visible until the phone is rotated back to the previous position. It is also important to make sure the on-screen keyboard is not visible when launching Waydroid; if it is, Waydroid will leave the space occupied by the keyboard empty.

Specifications and performance

The PinePhone has a 151mm (5.95in.) diagonal, 1440x720 capacitive touchscreen. The Allwinner A64 system-on-chip running the phone contains a quad-core, 64-bit Arm CPU. The phone comes in two models; the one I purchased has 3GB RAM and 64GB eMMC; the other model has 2GB RAM and 32GB eMMC. The 3GB model costs $200, while the 2GB one costs $150. Both models can use (and boot from) a microSD card of up to 2TB in size.

The phone boots from the microSD card if a bootable card is found. This is helpful when making changes to important parts of the operating system, because it makes the phone almost unbrickable. It is possible to brick the cell modem, but accidentally doing so is highly unlikely unless you try to reflash the proprietary modem firmware.

The PinePhone, like most smartphones until fairly recently, has two cameras: one front "selfie" camera and one rear camera. The front camera has a 2 megapixel (MP) sensor, while the rear camera has a 5MP sensor. Currently, the front camera takes poor-quality pictures that usually have a green tint and are often severely out of focus, while the rear camera seems comparable to that of an inexpensive Android smartphone. However, improvements to the postprocessing software are likely to significantly improve image quality in the future. Both cameras on my PinePhone have several dead pixels, but they are not noticeable in most pictures. The rear camera has an LED flash which also functions as a flashlight.

For me, using DanctNIX with Phosh with intermittent light use, the PinePhone's battery lasts for almost a whole day. Of course, this will vary with different distributions and workloads. I usually charge it occasionally throughout the day, but I could probably use it for a full day without charging if I reduced the screen brightness and/or used the phone less often.

The hardware supports WiFi, Bluetooth, and cellular (2G GSM, 3G UMTS, and 4G LTE). WiFi works as expected; it can connect to networks just like any other phone or computer, though only 2.4 GHz is supported. For me, 4G LTE voice, SMS, MMS, and data work fine. I use it with a T-Mobile-compatible Tracfone SIM card. Unfortunately, some carriers are not compatible with the PinePhone. It is best to check the carrier support page on the PINE64 wiki. Bluetooth audio output works well for playing music (both from MP3s stored on the phone and streaming over the Internet). I have not tested it for calls, nor have I tested audio input.

Security and privacy

The PinePhone's security is comparable to that of a Linux laptop with Secure Boot disabled. Apps are not containerized or isolated by default, but normal Linux security mechanisms apply. There have been some reports of PinePhone-specific malware, but avoiding software from unknown sources is a good way to protect against that kind of problem, as with desktop Linux. Most distributions optionally support full-disk encryption, as well, to protect phone data when the phone is turned off.

Privacy with a PinePhone is also basically the same as with a Linux desktop or laptop. Carriers can obtain approximate location information from cell tower triangulation, but this is inherent in the design of cellular networks and cannot be prevented by the phone other than by disconnecting from the cell network.

The phone does have several hardware privacy switches, found behind the battery cover. They can be used to disable the cellular modem and GPS receiver, WiFi/Bluetooth chip, microphone, and cameras. With the cellular/GPS and WiFi/Bluetooth switches turned off, it should be nearly impossible for the phone to be tracked by normal means. But, of course, virtually all electronic devices, even those with no communication hardware, produce radio-frequency emissions that could conceivably be tracked; other methods of tracking may also be possible.

Regular desktop web browsers are used, so any web trackers would work on a PinePhone just like they would on a desktop or laptop. However, because desktop browsers are used, extensions such as uBlock Origin and Privacy Badger work well.

Convergence

One of the features that I found most useful is convergence: the ability to use the phone as a desktop computer. The 3GB edition comes with a USB-C docking bar, which provides two USB-A ports, one HDMI output port, and one Ethernet port. It also includes a USB-C port for charging the phone. The dock can be purchased separately, presumably for use with the 2GB model. Alternatively, any USB-C hub that supports USB-C DisplayPort alt mode and has HDMI output should be compatible, although one without the ability to charge the phone from the hub would not be recommended due to the increased power usage while docked.

Any programs that are open on the phone screen can be easily moved to the monitor and vice versa. The video occasionally briefly disconnects and then comes back, but overall it works reasonably well; that problem may be due to the inexpensive TV I used as a monitor. Because all features of the phone still work, it is possible to send and receive text messages. Calling should also work, but because several cables are connected to the phone, using speakerphone or an external headset is probably necessary.

Development

Developing for the PinePhone is not much different from developing for any other 64-bit Arm device running Linux, such as a Raspberry Pi. Of course, applications must be designed to support small screens and touch input. Many desktop programs work fine with only scaling adjustments; others need more substantial changes.

GTK applications can use libhandy (for GTK 3) of libadwaita (for GTK 4) for improved mobile device compatibility. Qt apps can use Kirigami. A list of mobile Linux applications, LINMOBapps, is useful for both users and developers; for users, it is a way to find applications that run on the PinePhone; for developers, it is a way to find mobile Linux projects to contribute to.

Accessories and other devices

PINE64 has also created a new phone, the PinePhone Pro, which features a faster processor and increased RAM and eMMC compared to the original PinePhone. The PinePhone Pro costs $399; it is currently even more experimental than the PinePhone, so it is still mostly a developer device.

Several add-on devices for the PinePhone are available. These replace the phone's back cover, adding features such as wireless charging, fingerprint sensing, or an external hardware keyboard. The keyboard basically converts the phone into a small laptop and adds battery capacity to the device. It is important to note that the keyboard interferes with using the phone as a handset and with the convergence feature, so users who need those may be better off without it. More common accessories, such as cases and a screen protector, are also available, as well as development-focused devices such as a serial console adapter.

The PINE64 smartphones are not the only Linux phones available. Some models of Android phones can run regular Linux distributions in the form of custom ROMs, as mentioned earlier. There have also been previous attempts at creating FOSS-oriented smartphones, such as Openmoko. Purism has developed the Librem 5 Linux-based smartphone, but there have been long shipping delays with it. Also, the price tag ($1,199 for the base model, or $1,999 for the made-in-USA model) may discourage many potential customers from ordering the Librem 5.

Pine Store Ltd., which is the company that makes and sells PINE64 products, only makes hardware; the software is developed by the PINE64 community. The community is also involved in the design of the hardware, however. The PINE64 Philosophy page describes it this way:

A simplistic point of view, often offered up and referenced online, is that 'PINE64 does hardware while the community does the software'. While this depiction is not inaccurate, it is also a gross oversimplification. The fact that PINE64 is community driven doesn't simply entail a one-way reliance on the community or partner projects for software support; it means that the community gets to actively shape the devices, as well as the social platform, of PINE64 from the ground up.

Beyond just SBCs, phones, tablets, and laptops, Pine Store also makes devices such as an IP camera (PineCube) and a smartwatch (PineTime). All of these devices run almost exclusively FOSS by default as well.

In conclusion

The PinePhone is definitely different from most smartphones. It is closer in many ways to a regular Linux computer than to an Android smartphone or an iPhone. Having experience with Linux and a willingness to ignore some rough edges will both help in getting the most out of it, but it may be a good idea to keep another phone around for times when the PinePhone does not live up to the full smartphone experience that people have come to expect. For Linux users willing to ignore or work around these problems, the PinePhone is a device with a lot of potential.