Firmware is the code that runs directly on your RepOne Sensor to do things like calculate reps, display them on the OLED screen, communicate via Bluetooth, etc. If we want to fix bugs or add new features, we need to update the firmware. RepOne Sensor uses a custom built over the air (OTA) device firmware update (DFU) solution that works over Bluetooth Low Energy. This means you don't need to connect your RepOne Sensor to your local Wifi network, or do a direct Wifi connection with your mobile device. You can update with the same connection you're already using to do your workout.
As we improve the firmware and app, we'll be adding OTA DFU support for more phones and phone operating systems. In the meantime, you might experience problems where OTA DFU doesn't get past 0%, or gives an error toward the end of the upload process. If this happens, please send us an email with the phone model and operating system version so we can add it to our list. Many more phones work than don't, so here's a current list that has known issues. If you have one of these we suggest borrowing another device for firmware upload until we add support for your device.
Several Samsung Galaxy phone models
iPad Mini's with iOS 12 or earlier