Phone coverage-St. Kilda
We enquired about camping overnight to NT Scotland & were basically told "no chance". When we got there, we spoke to the ranger chap who meets you at the pier & he said we could've camped no problem, unfortunately we hadn't taken our gear, we'd left the tents pitched by the ferry terminal on North Uist.
You can't land from any covered boats (cabins) or any boats with lockers. There's no where to tie up alongside the pier. You either anchor off or pick up a mooring. The moorings are private for the day trip boats, but they are quite accommodating if you talk nicely. Either way, you need a tender.
You have to call up the ranger before landing & they will meet you at the pier & give you a pep talk.