Freecell
Four free cells, eight cascades, every card face up from the first second. Freecell is the solitaire you can always win if you think, and this is a clean, quick, full screen version of it that saves itself and never asks you to watch an advert.
The game
Fifty two cards are dealt into eight columns. You build the four foundations up from the ace in each suit, moving one card at a time, with the four free cells at the top left as parking spaces. Columns are built down in alternating colours. Because nothing is hidden, there is no luck once the deal is on the table, only planning: how many cards you can move as a group depends on how many cells and empty columns you have kept free, and the game does the arithmetic for you.
Drag a card or a run, or tap it and the game moves it to the best place. Undo is always there, and a game you leave is waiting when you come back. There is a tally of games played and won, and how long the wins took.
Three cells, four, or five
Four cells is the game. Three cells is the same deal with the safety net half removed, which turns a familiar game into a hard one. Five is gentler, for a phone in a queue. Timed play adds a finishing bonus for speed. Tournament scoring, for people who want a number to chase, pays for each card sent home and charges for taking one back or leaning on undo. All of it is optional; the plain game with nothing but a win is the default.
If you remember Freecell on Windows
Freecell reached most of the world as the second solitaire that came with Windows, first as an extra for Windows 3.1 and then on every desktop from Windows 95 onward, until it went missing from Windows 8. The original had thirty two thousand numbered deals, and the point of the number was a boast: every one of them could be won. Nearly true. Deal 11982 cannot be, and people who played the game for years still remember that number. There was a cartoon king in the corner who watched you play and smiled when you won, and there was no undo, so a wrong move was a wrong move.
Follow Suit keeps the game itself exactly as it was: the same eight columns and four cells, the same rule about how many cards may move at once. It fits whatever screen you have, from a phone held upright to a television, and adds undo, an optional clock and optional scoring for the people who want them. Deals here are shuffled fresh, so the old numbered deals are not reproduced yet; that is on the list.
Anywhere, free
Freecell runs entirely on your device: no connection needed once the page has loaded, and nothing about your game is sent anywhere. On a phone you can add it to your home screen and it opens like an app. There is a desktop app for Windows and Linux. An account is optional and only carries your statistics and settings between devices. The same site has Klondike solitaire, and Spades and Hearts to play with friends by a four-letter code.