Enter the Matrix
It can often be a struggle to assess and treat the cognition of a client with severe aphasia or other communication impairment. An app I have found especially useful in this area is called MatrixMatch 2. It used to be called Matrix Game, but a recent update changed the name in addition to adding three new levels. Similar to the popular tests Raven's Colored Progressive Matrices (RCPM) and Test of Non-Verbal Intelligence (TONI), this app does not require any verbal instructions or output to work on non-verbal reasoning and problem solving.
A card with a complex shape appears on the left-hand side of the screen next to a matrix of simpler shapes. The user's task is to drag the card to the empty square in which the overlap of the shapes in the vertical and horizontal rows forms the combination shape on the card. Each level has 16 cards, and there are 12 levels in the full version of the app. Errors are bounced back rather than accepted, providing an errorless learning format. Sounds are fairly gentle, reminiscent of a space ship, to indicate correct and incorrect answers. While most levels feature various shapes (lines, dots, small vs large, black vs white), one of the new levels features numbers.
MatrixMatch 2 is a free download, allowing you to try two levels, but the $0.99 upgrade to unlock all 12 levels is well worth it. The only childish features are the intro music (which can be muted on the second screen) and the cheering when the level is complete. The app states it is designed for children over 6 years of age to develop visual perceptual skills, attention, and categorization as well as planning and perseverance. In addition to the stated goals, I have used this app to target goals in non-verbal reasoning, sustained attention, and visual attention. It could also be used for verbal goals such as naming ("circle"), giving directions ("find the horizontal line"), and high-level describing ("white upside-down triangle over a dark oval").
Despite being designed by MyFirstApp.com for children, this app can be very challenging for adults in a rehab setting. It is not a particularly fun app (perhaps why they removed the word "Game" from the title), but it is good therapy. I highly recommend it to SLPs to check for deficits in nonverbal reasoning and to train this process, so important for using compensatory language strategies.