Many games meet the FIVES criteria for being highly interactive, visually supportive of language formulation, and geared toward addressing "Speechie" objectives such as categorization, sequencing, and interpretation of body language. Some additional factors I take into consideration are language neutrality (does the app work like a wordless picture book as a context to elicit language) and pace/timing (can the action be stopped by pausing or taking the iPad away for a moment to discuss?).
Though this is almost too late to make it useful for Halloween use (you can of course continue the app into the following week for "Halloweeen season"), I wanted to feature the app Haunt the House ($1.99)! Sort of a stepped-up version of Toca Boo!, this app has you act the role of a ghost attempting to scare people out of various settings including a village, mansion and train. The ghost can "possess" items in each room, prompting predictions about object function.
Using apps such as these with students is a good opportunity to target executive function and Social Thinking® applications around monitoring time and turns. My students yesterday posed that a fair turn would be 6 minutes! We limited them to 1-minute turns (with a timer) and then asked "how long that felt" to play or wait for a turn--it's plenty. The timer or clock can then be faded or facilitated for independent use.
We used this app with several pre/post activities:
-A mini lesson about "thinking with the eyes" and physical proximity (body in the group). You know you are being successful at scaring residents when they "notice" the object's movement with their eyes, and the best strategy is to move to rooms where people are present.
-From memory, I asked my students to create a map of the house, thereby targeting the story grammar element of setting and the executive function skill of mapping a space one is to navigate (see the work of Sara Ward and Kristen Jacobsen). I scaffolded by placing a few "anchor" rooms on the map so the students had a model of how to sketch, as well as a place to start.