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To delete the a touchcast simply touch the one you want to delete and then scroll down to the "More Actions" button.
You will notice that he option changes depending on where the touchcast is currently stored.
Below is an example of a touchcast that is stored locally and within Fabric, you have the option to delete from iPad and Fabric.
Note if you delete from iPad you can still can share your touchcast from Fabric, it will just free space on your iPads storage.
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