I've been tempted to hack together a web based game. It will be some simple puzzles requiring working memory, like that addition of numbers example. It could even be word problems with multiple choice answers, but the questions has to be relatively wordy with several data points to consider. Periodically it will get interrupted, by several things, but mainly a face with a speech bubble, asking various questions like "are you busy?", "can I ask you a question?", "how much longer do you think you will take to complete this?". This will completely take over the screen and you won't see your last question. You can select some answers (yes, no, 5 minutes, etc.) and some answers will lead to more questions especially if you give wrong answers. Also questions that you need to visualise to come up with an answer, like comparison of sizes or distances of things you don't often compare (bus vs yacht) After each interruption you will return to your puzzle game. The first interruption will only kick in after a while so you get used to how easy it is without interruptions, but then they'll start to kick in frequently but also randomly so you have some breaks sometime but never know for how long.