First, make sure you are working with a compatible app:

http://airturn.com/ipad-apps/

Next, make sure you don't have too many apps open:

http://airturn.com/bt-105-faqs/1-easy-ipad-bt-105-fix

Next, try rebooting the network settings for both your BT-105 and your iPad - clearing the network cache can make a big difference in performance, and many times will re-establish proper connections between the BT-105 and the iPad:

http://airturn.com/bt-105-faqs/resetting-bluetooth-connections-between-the-airturn-bt-105-and-the-ipad

Finally, make sure your BT-105's profile is set to "iPad mode":

http://airturn.com/bt-105-faqs/changing-keyboard-profiles-with-the-bt-105-v-122

On occasion, the iPad app itself may need to uninstalled and reinstalled, but only as a last resort.