My go-to mobile game for time-filling fun used to be Drop 7. Then it was Threes. These days it's Sage Solitaire, a new riff on solitaire from the ever-interesting developer Zach Gage. I'm making pairs, straights and flushes, often while listening to a podcast. I'm hooked!
The game's default mode is free, and it's fun enough. If you pay $5 you can access a two-deck mode and a "Fifteens" mode, both of which I show in the video above.
If you have an iOS device, give this game a shot. Gage says he's working on an Android version next but doesn't know when it will be ready. Sounds like it will be a matter of weeks.