"Backwards compatibility
Bluetooth 3.0 is backwards-compatible. This means you can keep all of your current Bluetooth-enabled devices. This backward compatibility is enabled via a 2.4 GHz Bluetooth radio in addition to the Bluetooth 3.0 radio chip. However, note that transfer speeds are only as fast as the slowest device, which means that if your Bluetooth 3.0 device is connected to a Bluetooth 2.1 device, your transfer rate will be limited to 2.1 mbps."
https://developer.att.com/developer/forward.jsp?passedItemId=200140
I have an Android 4.04 tablet (Aluratek AT208F) and I am trying to pair it with an Anker ultraslim keyboard. But one factor that was not advertised about the Anker is that it is Bluetooth 3.0 while my tablet is 2.1. So while I am able to connect the devices, thereafter I am unable to get them to talk to one another. Is this a Bluetooth backwards compatibility issue?
I hope to test the Anker with some Apple devices in another couple of days, but right now my tablet is the only Bluetooth compatible device near to hand with which to test the keyboard. However, I have previously tested the tablet with an older iPad centric Bluetooth keyboard, and it worked fine in the brief test.
Thanks in advance!

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