Titanium backup and Ad Away are my fave but plenty of other things.
I've got a keyboard with track pad. I bought it a couple years ago, so I don't remember where I got it from. Pretty sure its not a Samsung one. It's decent and works to write longer emails on the road.
Being patient is where it's at. In any case, many sellers include the "free" shipping in their costs, so it’s not rare to find a say a $20 item with Prime for $215 plus $5 shipping with another seller.
Amazon often has free shipping over $25 so over the months we just slowly add items in our cart, then buy by just over $25 increments to get free shipping.