Here you will find links to manufacturers' support or download pages where you can find the latest firmware and updates. You can also go directly to each manufacturer's website if you cannot find what you are looking for here.
Angelbird: https://www.angelbird.com/firmware-update/
Atomos: https://www.atomos.com/product-support/
Boya: https://boya-mic.com/download
Brinno: https://brinno.com/pages/support-support-center
Celestron: https://www.celestron.com/pages/support
Chasing: https://www.chasing.com/en/service-support.html
DataVideo: https://datavideo.com/global/page/support
Feelworld: https://feelworld.ltd/blogs/news/tagged/firmware-update
Hikmicro: https://www.hikmicrotech.com/en/support/download-center/firmware-download/?activeTab=Firmware
Hobolite: https://www.hobolite.com/pages/hobolite-app
Hollyland: https://www.hollyland.com/support-home
Ilford Photo: https://www.ilfordphoto.com/health-and-safety/?___store=ilford_brochure&___from_store=ilford_uk
OWC: https://eshop.macsales.com/tech_center/basictrob.cfm
Kodak: https://www.kodak.com/en/consumer/page/support/
Lexar: https://www.lexar.com/download_cat/download-en-gb/
Nanlite: https://www.nanlite.com/service-product?t=1712914189337#/en
Nanlux: https://www.nanlux.com/service-product?t=1712916130751#/en
Nissin: https://www.nissindigital.com/product
Panasonic: https://av.jpn.support.panasonic.com/support/global/cs/dsc/index.html
Polaroid: https://support.polaroid.com/hc/en-us
Rhino: https://rhinocameragear.helpdocs.io/
Ricoh/Pentax: https://www.ricoh-imaging.co.jp/english/support/
Samyang: https://www.lksamyang.com/en/support/support-main.php
Saramonic: https://saramonicusa.com/firmware-downloads/
Tamron: https://www.tamron.com/global/consumer/support/download/
Tokina: https://tokinalens.com/support/downloads/
TourBox: https://www.tourboxtech.com/en/downloads.html
Transcend: https://www.transcend-info.com/support/service
Vaxis: https://www.vaxisglobal.com/Download-n1304021.html
Zeiss: https://www.zeiss.com/consumer-products/us/service/download-center.html
Zhiyun: https://www.zhiyun-tech.com/en/download/product?type=website&page=header&source=download#/pages/download/index/index