Grand arena omicron

Some Omicrons do in fact cost 10 in the game, however, it is not dependent on what kind of phone you have. Rather, the omicrons that cost 10 specify the only work in either 3v3 or 5v5 of Grand Arena, not both, which is why they only cost 10. All the others that work in both cost 20 because they work in both game modes. If this is not the reason then there may be a glitch of some kind.