The player you send the gift to must have the latest update of Word Chums in order to see the gifts. You may need to let them know to head to the App Store and apply the update. The gifts will be in their inventory after the upgrade.
To see inventory you just tap your chum, select inventory, and then tap on items you would like to wear.
The boost on a gift is based on the person receiving the gift. Its always a little better boost than a person could buy in the regular store items at their current level. So...when you gift an item to someone the boost % may be very different than it is on the item for you.
Thanks for your support!