Old Android phones make better smart home wall panels than any $200 displays

Published Oct 8, 2026, 10:01 AM EDT Ayush Pande is a PC hardware and gaming writer. When he's not working on a new article, you can find him with his head stuck inside a PC or tinkering with a server operating system. Besides computing, his interests include spending hours in long RPGs, yelling at his friends in co-op games, and practicing guitar. When you’ve got dozens of smart home gadgets lying around, you’ll want a means to control them. Trigger-action automations work pretty well for devices when you want the smart devices to manage themselves, and you can always whip out a smartphone and use the IoT companion apps to manually tweak certain settings. That said, wall panels featuring all sorts of toggles work just as well, especially when you want an all-in-one smart home dashboard. Unfortunately, decent wall panel models can cost upwards of $200. Worse still, you might still have to work with locked-down ecosystems on your premium control pad. As someone who loves repurposing old devices, I have to admit that old smartphones (and tablets) make for better control hubs than actual wall panels, especially when you combine them with the likes of Home Assistant. A smartphone display can serve as a customizable dashboard for Home Assistant Especially once you add Bubble Card templates into the mix At the core of this project lies the Companion App for Home Assistant, which even lets you boot directly into a dashboard instead of the usual application launcher. As for the UI, Home Assistant has a default dashboard interface that often displays the sensors, smart gadgets, and IoT paraphernalia in different parts of your living space. But it’s not the only one you get on this platform. In fact, you can design completely new dashboards featuring only those components that you wish to see on your DIY screen panel. And for smart products that need controls, you can rely on the Bubble Card collection from the Home Assistant Community Store to design compact UI cards. Rather than tossing everything in haphazardly and making a messy UI that’s too convoluted to use with the makeshift Android control hub, Bubble Card provides neat pop-up actions for each component. Let’s say you want to control a bunch of smart lights. Creating a Bubble Card for each light source lets you add the controls directly into the entity. Personally, I’ve also configured horizontal button stacks for a couple of ESP32-powered devices, so I can map even more actions to them. Considering the sheer number of customizability options on Bubble Card, I have to admit that it can get a little overwhelming at first. But with a little bit of fine-tuning, it becomes a solid option for mapping entities and their controls to a smartphone-turned-smart panel. Old smartphones have more sensors than conventional smart displays The HASS Companion App lets you use them as any ol’ entities So far, I’ve only discussed the control and monitoring aspect of the smart panel. But since the Home Assistant Community App can pull stats from the smartphone, your panel itself can serve as an entity. And with all the sensors built into modern smartphones, that opens doors to some quirky workflows. Take the Bluetooth support, for example. With a handful of settings, you can have your smartphone serve as a monitor for all the paired Bluetooth devices. Or, you could go full-throttle into the network connectivity rabbit hole, and use your Wi-Fi signals to detect presence, check uptime stats for home lab nodes, or read other wireless information that you can use to trigger automation rules. Combine its camera with an app that can enable ONVIF streams and connect it to a Frigate container running on your home server, and you’ve got a makeshift surveillance camera built from your smart panel. And since Frigate has a rock-solid (unofficial) integration on HASS, you can even use the motion detection provisions on the former to drive automation pipelines on your smart home hub. With some tweaks, it can even provide voice assistant functionality Toss in some AI models, and you’ve got a fully local voice control pipeline Technically, you can combine the Assist tool on HASS with LLMs to query them about your Home Assistant devices, and it works pretty darn well even with tiny AI models. But the entire query workflow would be text-based, and you’d have to type everything manually into your makeshift smart panel. Fortunately, it’s possible to build a reliable voice assistant with this setup, especially with the talented Home Assistant devs releasing a QoL update earlier this year. Up until a few months ago, building a DIY voice assistant on HASS used to be a bit of a pain. Besides the AI part of the setup (which is arguably somewhat easy thanks to certain integrations), you’d have to set up a workflow that accepts wake words and springs the voice assistant pipeline to life. Typically, this used to involve Raspberry Pi boards or even ESP32 microcontrollers alongside dedicated microphone and speaker setups. But around March 2026, Home Assistant added the voice satellite functionality to smartphones, allowing your pocket-sized companion to process wake words without requiring extra hardware, effectively getting rid of the extra hoops you’d have to jump through to activate the voice assistant. You can use local LLMs to power this voice assistant under the hood If you’re wondering, my current setup uses a Gemma-4-E4B running on an old GPU alongside the TTS and STT apps on Home Assistant – with my smartphone serving as the voice satellite. Getting my LLM working on HASS wasn’t as easy as using the built-in integrations, as I’ve got Gemma-4-E4B deployed on a llama.cpp container instead of a bloated Ollama instance. But thanks to the Home Agent integration on HACS, I was able to pair my llama-server’s backend with the smart home platform. As for its performance, Gemma-4-E4B is light enough to run at 40-50 tokens/second on my GTX 1080, so the entire pipeline is extremely responsive. Likewise, my voice assistant gets pretty much most of my queries right on the very first attempt. Of course, my lightweight LLM would buckle under the extra reasoning load if I tried using it to create automation rules. But for simple queries involving smart home gizmos, it meshes well with the microphone and speakers on my smartphone-powered control panel. Home Assistant OS Windows, macOS, Linux iOS compatible Yes Android compatible Yes