Card game Five Hundred was invented in US in the early 1900s. As its predecessor Euchre, it extends the trump suit by using special cards (Joker, Right and Left Bowers), while at the same time involves a bidding system similar to the one used in Bridge, as well as provides a kitty for the contractor to exchange unwanted cards. The game is especially popular in Australia, where it is has become the national card game.

Though 500 is often viewed as a partnership game for 4 or 6 players, it was originally designed as an individual 3-player game, and, according to card game experts, the game is most exciting in this form, where each player can demonstrate their analytical skills to the full.

This application implements a three-player version of game 500 with one human and two computer players. Since, to our best knowledge, the game has no official rules, while various sources provide different, often controversial descriptions of the game, the application allows to modify game rules to suit your expectations. These modifications affect scoring system, presence of Joker, conditions of own overbid, limitations on bidding Misère (Nullo) and leading with Joker in a non-trump game, style (or absence) of All-Pass games etc.

In addition to rule modifications 500+plus allows to set up appearance of the game (e.g. background image, style of face cards, picture of card back), customise sound effects, and specify play list for custom background music.

The game can be also played over the network (local or Game Center) against one or two network players. Voice chat is supported over Game Center network.

500+plus keeps summaries, local score tables and achievements. As an option, these data can be kept or synchronized between devices using iCloud. High scores and achievements can be also submited to Apple Game Center tables online.

For those who are new to the game, the application offers a detailed description of game rules. Other information pages are included, like rule modifications (tweaks) and settings, game control etc