Cast your music to smart speakers around your home using AirPlay, Chromecast or to your Alexa devices.
Open the Alexa app.
Select "More" from the bottom menu, then select "Settings" then "Devices Settings"
Select your echo device from the list, then under Bluetooth Connections select "Connect a device".
Open up the iOS Settings app, then select Bluetooth
Select your Alexa device from the list. The device will then announce that "it is now connected to (Your) iPad".
Once paired, you can go ahead and close both the Settings app and the Alexa app.
Once you are paired to the Alexa device you can rename it by tapping the "i" under Settings>Bluetooth and rename the device to something more memorable.
If you have connected via Bluetooth to this device before, sometimes the iPad / iPhone won't connect to it again. This is an iOS Bluetooth issue.
Tap the "i" icon next to the name and choose "Forget this device". Then rescan for Bluetooth devices and select it. It should now pair for you.