VoxAlti uses Wi-Fi to carry out updates. The FDS Altis app (available on iOS or Android) needs to be used first to set the Wi-Fi network name and password on the altimeter. After settings those, use the .bin file at the bottom of this page and follow the instructions in the instructional video found here:
Firmware Version 1.3 (March 8, 2026) Lower power optimization and fixed pre-jump brief glitch on ascent. VoxAlti_Firmware_1_3.bin