I have used the the RadTech ClearCal. They are supposed to be removable and re installable but I was not able to re install it without bubbles.
I tried it originally to reduce the screen glare as I use the iPad so much for reading and it worked well but it did get finger prints more easily so I removed it for a test and then was unable to reinstall it without a lot of bubbles and messed up my second sheet so I reordered. The bottom line is that they work well but they are not fingerprint resistant like the ipad glass.
Mary D
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