Yes we have a rule on this!!! We spenr much valuable time debating this at a recent AGM.
1)The scorer must toss the coin, the first named player will call whilst the coin is in the air.
Personally I will never call whilst the coin is in the air where any 'tosser' is going to catch the coin (and vice versa if the opposition is calling). Almost all are honest 'tossers', but I've seen the coin flipped in the hand. I prefer to let the coin drop rule or not.
The point of this rule was to prevent scorers taking a coin striaght out of their pocket and banging it on the table.
Inventor of the Triangles version of Bar Billiards. Highest England away aggregate 2013 and 2014, 10 - 0 last 10 England singles legs, seventh reserve 2015. Jersey Qtr final 2014, 2015, 2016 - Guernsey Plate Winner 2014, Main Final 2015, 2017. First person to have won both four pin opens.