Hi,
@sflannery , another thing to try is shaving the application area. Even people who don't have particularly hairy arms will often still have a fine peach fuzz, and that growing under the sensor won't be doing it any favours in stickiness, so best to wash the area, shave, leave to fully dry, and then use the alcohol wipes to get rid of any remaining grease.
Also, one thing which surprised me in the first week or two of using libre was the number of times I'd inadvertently bump up against doorjambs without realising it. Tore one off that way. As a newbie to libre I wore the first few on the side of the arm but soon realised that putting it further round the back of the arm gave it more protection, and I started paying more attention when going through doors.
Same goes for taking jackets, rucksacks and seatbelts on and off - it can be surprisingly easy just to catch the edge which will loosen it over time.
I've never had to use Skintac, but it regularly gets good recommendations.
I normally put a 7 by 8cm Molnlycke Mepore plaster (about 20p in Boots) on top just to smooth out the edges, less prone to catching.
Good luck!