Developer with BLE experience. Update my mobile app (iOS + Android). — 2

I own a wearable tech company (www.spacebands.co.uk) and we have an android and iOS app that our users must use to update the settings of their device.
At the moment, users can only edit one device at a time, I want to allow users to edit multiple device settings at the same time.
The app functions well and I have created designs already to enable multiple device editing.
I need to hire a developer who can update my app (both iOS and Android) with capability to edit multiple devices at once. Our devices are connected via Bluetooth.
I have attached some previews of the files.

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