Best [Insert row / Remove row] user action for table on touch screen

Question

I have to code a widget displaying a table on a touch screen and I'm wondering what is commonly used to do so? I thought about holding click down between two rows to insert and holding click down on a row to remove it, just like this:

Since it's my first time in the touch screen world, how can I make it intuitive and help the user to "guess" the way he can insert and remove? Because on a regular computer I'd pop some kind of tooltip, if the key stops to move, but touch screens are different because finger is not held when moving.

Answer 1

Couple of solutions, obviously there's no indication of the space and the user base you're working to. Left screen shows a gesture only type scenario, 2nd and 3rd screens show button based versions.

Answer 2

Assuming a person in front of an empty table will want to add stuff into it (even more likely if this person got in front of this table on purpose), I think a worker will try to hold his finger on the screen and then I can display a circle menu strip, up to insert above, down to insert below, and something else to remove!