Definitely add multiplayer
It’ll definitely make more people get this game if it has multiplayer my family included because we all play at christmas all night long every year. Because it’s practically the only time we can. If this had multiplayer I will 100% tell them about it and could quite potentially get them to get it. Even better if it had voice chat where all four players can hear each other because its hard to get a read on people when it’s silent but i mean it isn’t that important as friends and family could simply do a group call. As well as a friend system to make it easy to play with friends and family. I think this will definitely make it more popular especially if you can somehow partner up with facebook some how and make it kinda like 8 ball pull where its easy to match up with friends. Then it’ll be easier for people to find it. If its money you want then simply make the app free and have in app purchases such as backgrounds and cards and possibly charge a little more for something like custom back grounds and card where people can use images from their phones to customize their cards and background. These are all just suggestions but definitely add multiplayer.