ItsDeductible Online is a platform for entering donations during the year. It has smartphone apps that interface with the web site; anything you enter via the web should be visible in the app and vice versa (assuming you are using the same login account.)
Turbotax, both the online version and the desktop program, can import donations from ItsDeductible online (Deluxe version and higher). However, you must use the same user account for ItsDeductible and Turbotax (all Intuit sites use single unified login).
Also, you will probably see that the values of the items change between ItsDeductible and after they are imported into Turbotax. The official explanation is that the values in ItsDeductible Online are preliminary estimates, and the items get converted to their final values when you import them into Turbotax.
You can also enter item donations directly into Turbotax if you prefer. And certain items (like vehicles, and other items worth more than $500) can only be entered in Turbotax, not ItsDeductible. Do the ItsDeductible import first then add your additional items.