Flow is a puzzle game for the iPhone and iPad where you have to connect matching colors with a pipe to create a flow. The catch is that these pipes will break if they cross or overlap, so you must find the perfect paths that allow all pipes to be created even though some of them will not be taking the shortest route.
So that's the objective of Flow: connect all the dots to create matching pairs and fill up the entire board. For most levels, filling up the board isn't an issue, but every once in awhile you'll encounter a level where it's possible to create all the pipes without using the entire board.
There are two different game modes: free play and time trial. In free play, you have as much time as you want for each level, but the goal is to complete each level in as few moves as possible. In time trial, your goal is to pass as many level as possible in 30 seconds, 1 minute, 2 minutes, or 4 minutes.
Flow comes with 5 different board sizes for iPhone: 5x5, 6x6, 7x7, 8x8, and 9x9. It also comes with 5 board sizes for the iPad: 10x10, 11x11, 12x12, 13x13, and 14x14. All off these board sizes include 30 levels, which means that Flow comes with a total of 300 levels for free.
The free version of Flow is ad supported, but if you purchase any level packs, each of which contain an addition 150 levels for $0.99, the ads will be removed. There is a total of three level packs available. Unfortunately, there isn't a discounted "all levels" pack available.
Flow for iPhone and iPad is a really fun puzzle game for the iPhone and iPad. The goal is extremely easy to understand and the beginning levels do a great job of not being too difficult, but as you progress through the game, the levels become quite challenging, especially on the huge iPad levels.