I agree with this post. I'd like to have the choice to auto connect or not. I don't understand the logic in Eventide's response. Connecting doesn't cause any changes to the H9.

Bohan's post was a bit unclear.  Here's the deal with auto connecting. 

There is no way to initiate an auto connection from an iOS device to an H9.  The H9 is using Bluetooth 2.1 which works through Apple's external accessory framework, and that doesn't give apps a way to connect to a device.  On Android apps can initiate connections to Bluetooth 2 devices, and we do auto connect on Android.  If the H9 were using Bluetooth LE, there would be a way to autoconnect from the app on iOS as well, but that's a different kind of Bluetooth chip.

It would be possible to try to auto connect from the H9 to the last paired device and we experimented with this as a feature for a while, but this is a much less attractive option that having the app auto connect to the device.  The problem with this is that sometimes an H9 would latch on to one device and you couldn't get it to let go of that device.  And if you tried to connect to it with another device, you couldn't.  So, you'd try to connect to your H9 with your iPad for example, but you couldn't because unbeknownst to you it had auto connected to your iPhone.  This lead to a fair amount of user confusion where users thought the Bluetooth on their H9 was broken.