4-inch square HDMI displays with USB touchscreen sell for $33 and up

We’ve already seen some small HDMI displays, mostly useful for SBCs like Raspberry Pi boards, including a 7-inch monitor with a stand, a 7-inch HDMI touchscreen display, and a 7.9-inch ultrawide HDMI display.

Today, I’ve come across another form factor with two 4-inch square HDMI touchscreen displays with 720×720 resolution: the VIEWE model appears to be new and is the cheaper of the two at about $33, while the Waveshare “4inch HDMI LCD (C)” has been around for a couple of years and offers extra features such as a 3.5 mm audio jack and speakers support, and mounting for Raspberry Pi 3/4/5 single board computers with adapters.

VIEWE 4-inch square HDMI touchscreen display

VIEWE 4-inch HDMI display (UEDX72720040-HMD-RB-A) specifications:

• Display
  • 4-inch square HDMI TFT display with 720×720 resolution
  • ST7703 display driver
  • Brightness – 300 cd/㎡
  • Active area – 71.93 x 71.93 mm
• Touchscreen – 5-point capacitive touch screen via USB-C port; FT6336U touch IC
• Video Input – HDMI 1.4
• Display Interfaces via Lontium LT6911C HDMI to MIPI DSI/LVDS chip
  • Single/Dual-Port MIPI DSI/CSI transmitter
  • Single/Dual-Port LVDS transmitter (connector present but not used with the provided 4-inch MIPI display)
• USB – USB-C port for power and touchscreen
• Dimensions – 84 x 84 mm
• Temperature Range – -20 to 70°C

The product page has some documentation. You can allegedly connect the display to a computer’s HDMI port and a spare USB port, and it will just work. For Raspberry Pi boards, you’ll need to edit the /boot/config.txt file as follows:

The main selling point of the VIEWE 4-inch HDMI touchscreen display is its low price since it goes for $33 on AliExpress, or even less since I’ve offered a $28 promotion as a “new user” (albeit logged in).

As a side note, I had never heard of VIEWE until a few months ago, and they also make some display solutions based on ESP32 SoCs that look similar to products from competitors like Waveshare, LILYGO, and Makerfabs. They also have a GitHub account for their programmable displays.

Waveshare 4inch HDMI LCD (C)

If you’d rather get a 4-inch HDMI touchscreen display from a better-known company, or at least on this side of the Internet, the Waveshare “4inch HDMI LCD (C)” is another option that has been around for a while, but we hadn’t covered it so far.

Specifications:

• Display
  • 4-inch IPS display with 720 x 720 resolution
  • 170° viewing angle
  • Active area – 72.53 x 72.53 mm
  • Realtek RTD2660H flat panel display controller
• Touchscreen – 5-point capacitive touch screen via USB-C port or I2C; toughened glass panel, hardness up to 6H.
• Video Input – HDMI 1.4 via micro HDMI or full HDMI adapter
• Audio – 3.5mm audio jack and 4-pin speaker connector, both using HDMI audio input
• USB – USB-C port for power and touchscreen (if USB selected)
• Misc
  • Five buttons for OSD: Exit, Down/Right, Up/Left, Menu, and Power
  • USB/I2C touch switch
  • Pogo pins for connection with the Pi board.
• Dimensions – 84 x 84 mm

Waveshare says the display works/has been tested with Raspberry Pi OS, Ubuntu, Kali, and Retropie on Raspberry Pi boards, Ubuntu on the Jetson Nano, and Windows 11/10/8.1/8/7 with computers. Other operating system/host combinations may work, but your mileage may vary.

The /boot/config.txt configuration file needs to be modified on Raspberry Pi OS:

You’ll notice three different overlay files for the Raspberry Pi 3, 4, and 5 Model B boards. Those can be downloaded from the wiki, which also provides additional information to get started with the small HDMI touchscreen display.

Waveshare’s “4inch HDMI LCD (C)” ships with a micro HDMI to HDMI adapter for Pi 4/5, an HDMI to HDMI adapter for Pi 3, two USB cables, four standoffs, and four screws.  The Waveshare model is better integrated than the VIEWE display, as it requires fewer cables, supports direct mounting of the Raspberry Pi SBC, and audio output. It also features an IPS panel instead of the TFT one, which may explain the price difference, since the “4inch HDMI LCD (C)” costs about double at $66 on the Waveshare store. Alternatively, you’ll also find it on AliExpress ($69.29) and Amazon ($75.99).

Support CNX Software! Donate via cryptocurrencies, become a Patron on Patreon, or purchase goods on Amazon or Aliexpress. We also use affiliate links in articles to earn commissions if you make a purchase after clicking on those links.